Experimental Physics Division

Report of Activities in the Divisions

Annual Report 2000 – Volume II

Theoretical Physics Division ...... 1

Experimental Physics Division...... 5 The LEP Programme ...... 5 The LHC Programme ...... 24 The SPS Fixed-Target Programme ...... 47 CNGS Programme ...... 62 East Hall Programme ...... 64 AD Programme ...... 69 The ISOLDE Programme ...... 71 R&D Projects ...... 100 Other Experiments ...... 109 Technical Developments ...... 112

Information Technology Division ...... 127 Overview ...... 127 Physics Data Processing ...... 129 Technical Services ...... 132 Applications for Physics and Infrastructure ...... 136 Databases ...... 139 Communications Systems ...... 141 User Support ...... 145 Computing for Engineers ...... 146 Controls ...... 148 Internet Services ...... 151

Education and Technology Transfer Division ...... 153 Education and Communication ...... 153 Communities ...... 155 Library and Archives ...... 156 Information Support Unit ...... 157 Technology Transfer ...... 158 Intellectual Property Rights ...... 163

Large Hadron Collider Division ...... 167 Cryogenics for Accelerators ...... 167 Cryogenics for Experiments and Test Areas ...... 169

Contents iii Main Magnets and Superconductors ...... 172 Insertions, Correctors and Protection ...... 176 Magnet Test and Analysis ...... 178 Cryostats and Ring Integration ...... 179 Vacuum ...... 181 Industrial Automation and Supervision ...... 183

Proton Synchrotron Division ...... 185 Introduction ...... 185 Operation ...... 185 Lepton Operation ...... 189 Proton Operation ...... 189 Pb-Ion Operation ...... 190 Experimental Areas Operation ...... 191 ISOLDE ...... 192 nTOF ...... 195 Antiproton Programme ...... 196 Diagnostics ...... 198 Accelerator Controls ...... 199 Consolidation of the PS Complex ...... 200 PS Protons for LHC ...... 201 Ion Projects ...... 203 CLIC ...... 205 NUFACT (Neutrino Factory) Study ...... 210 Collaborations ...... 212

SPS + LEP Division ...... 215 Accelerator Physics ...... 215 Beam Instrumentation ...... 221 Beam Transfer ...... 224 Controls ...... 229 LHC Controls Project ...... 231 Cavity Technology ...... 233 Experimental Areas ...... 234 Emerging Energy Technologies ...... 237 SPS/LHC Radio Frequency ...... 238 LEP Radio Frequency ...... 243 Main Rings ...... 246 Resistive Magnets ...... 248 Operations ...... 251 Power Systems ...... 257

Technical Support Division ...... 257 Introduction ...... 257 Activities ...... 258 Reorganization Actions ...... 259 Management and Organization ...... 260

iv Contents Alarms and Access ...... 260 Civil Engineering ...... 262 Cooling and Ventilation ...... 264 Electrical Engineering ...... 270 Heavy Handling and Transport ...... 273 Monitoring and Operation ...... 275 Technical Facilities Management ...... 277

Technical Inspection & Safety Division ...... 281 Radiation Protection Group ...... 281 General Safety Group ...... 283 Technical Services and Environment Group ...... 284 Medical Service ...... 286 Fire Brigade ...... 287

Engineering Support and Technologies Division ...... 291 Introduction ...... 291 Administration and Planning ...... 292 Engineering Design Offices ...... 293 Engineering Support for Infrastructure ...... 293 Engineering Support for Machines ...... 296 Information Systems Support ...... 298 Logistics for LHC Experiments and Areas ...... 299 Manufacturing Facilities ...... 302 Surface and Materials Technologies ...... 304 Positioning, Metrology and Surveying ...... 307

Finance Division ...... 309 Introduction ...... 309 Accounting Services ...... 310 Implementation of the Budget ...... 310 Cash Position ...... 311 Pension Fund ...... 311 Visiting Research Teams ...... 311 LHC Collaborations ...... 312 Budget and Financial Planning ...... 312 Computing, Statistics, and Financial Database ...... 312

Supplies, Procurement and Logistics Division ...... 315 Introduction and Summary ...... 315 Purchasing Service ...... 316 Logistics and Stores ...... 316 Industrial Services ...... 317 Storage, Recuperation & Sales Service ...... 318 Informatics Support Section ...... 319 Exhibitions and Official Visits of National Industries ...... 320

Contents v Human Resources Division ...... 321 Human Resources Policy Issues ...... 321 Facts and Figures about Staff Members ...... 323 Facts and Figures about Fellows, Associates and Students Programmes ...... 325 Training and Development ...... 327 Equal Opportunities ...... 328 Social Security ...... 329 Voluntary Programmes ...... 331 About the Division ...... 332

Directorate Services Unit...... 335 Office of the Director-General ...... 335 Offices of the Directors ...... 335 Office of the Director of Administration ...... 335 Relations with Member States ...... 336 Council Secretariat ...... 337 Legal Service ...... 338 Internal Audit Service ...... 339 Strategic Planning Unit ...... 339

Administrative Support Division ...... 341 Corporate Information Systems ...... 341 Internet Development Services ...... 344 Systems and Application Services ...... 346 Organization and Procedures ...... 348 General Services ...... 349 Translation and Minutes Service ...... 350

Technological Developments at CERN in 2000 ...... 351

Seminars & Colloquia ...... 371

Training Programme 2000 ...... 389

CERN Schools ...... 399

Distinguished Visitors in 2000 ...... 405

vi Contents Theoretical Physics Division

During the last year the Theoretical Physics Division produced nearly four hundred research papers on a very broad collection of topics ranging from the more phenomenological to the more mathematical aspects of high-energy physics. It is impossible to even begin to provide a description of this breadth of interests, and we shall only give a glimpse of some of the subjects that have attracted more attention.

Continuing with a long tradition, phenomenology, both within and beyond the Standard Model, was the dominant activity carried out last year in the Division. It amounts to more than sixty per cent of the total production. The number of topics is staggering, and covers essentially every aspect of the subject. There was a rather consistent effort in the study of low-x physics, motivated in part by the large amount of existing data which requires a refinement of our theoretical understanding and which should play an important role in understanding LHC data. In the same vein, a rather thorough study was carried out of QCD tools at the Tevatron and LHC energies (parton densities, parton showers, two-loop radiative corrections, soft-gluon resummations, QCD backgrounds to Higgs production etc.). There have been many studies of Higgs production and decays, production of heavy quarks at high energies, b → sγ within the Standard Model and in a wide variety of supersymmetric extensions, top production and decays at the Tevatron and the LHC, jet activity in tt events and determination of the top quark mass, connections with cosmology regarding the search for dark matter candidates, rare K-decays, a renewed study of CP-violation within the Standard Model and some of its extensions, prompted by the ongoing experimental effort at K and B factories.

Members of the Division were active in the discussions concerning the evidence for a Higgs boson reported by the LEP experiments in the autumn of 2000, and in its possible interpretations.

Within the context of Beyond the Standard Model Physics, there were a number of research projects dedicated to the refinement of various supersymmetric extensions of the Standard Model, in particular the minimal one, MSSM, and others not necessarily preserving R-parity. In view of recent data, new boundaries in the parameter space of these models can be drawn, thus better delimiting the thresholds at which new supersymmetric physics could appear. Supersymmetry also produces a number of interesting dark matter candidates that have been studied in the light of new accelerator and astrophysical data. Significant emphasis was given to the study of how experiments at high-energy colliders can detect the existence of extra spatial dimensions. We have considered scenarios in which gravitons propagate in spaces with factorizable or non- factorizable geometries, and various models in which also Standard Model particles have Kaluza–Klein excitations. There was some activity in model building, some of it based on more traditional GUT methods, and some based on more novel ideas coming from open strings, branes and orientifolds. Although no viable model has yet been produced, the results are both encouraging and interesting.

Theoretical Physics Division 1 Another hot subject of current interest has to do with neutrino physics, their masses and oscillations. Refinements of the MSW mechanisms, solar anomalies, atmospheric neutrinos, models of neutrino masses and mixings were studied. The new models and data were also contrasted with older data such as that coming from supernova 1987A. This is an expanding subject in view of the new data now steadily coming in, and also with regard to the planning of new experiments under construction, or envisaged for the future, like the neutrino factory, and the eventual analysis of their results once they come on line.

Within the more theoretical aspects of high-energy physics, there was sustained work in the study of aspects of the AdS/CFT correspondence, and the supergravity duals of supersymmetric gauge theories, the study of brane physics and its connection with phenomenological brane-world scenarios, as well as various aspects of the Randall–Sundrum proposals and their generalizations. A field of rather intense activity in the Division was the study of properties of quantum field theory on noncommutative spaces. This is a very interesting subject which appears in particular decoupling limits of open string theory. Many of the intriguing properties of these theories were analysed. First of all field theories on quantum planes or quantum tori are nonlocal field theories appearing in a consistent decoupling limit of string theories; and although general nonlocal field theories are deemed inconsistent by standard wisdom, these theories have a very peculiar type of non-localities providing rather intriguing connections between the ultraviolet and infrared properties of the theory and are likely to provide novel tools to obtain nonperturbative information in Yang–Mills theories with and without supersymmetry.

Another subject which received increasing attention during the past year is the study of Boundary Conformal Field Theories (BCFTs) in various dimensions. Again these studies are inspired by the properties of the AdS/CFT correspondence and by the interactions between branes and open strings. BCFTs provide a rather powerful tool in these subjects as well as in the study of field theories on quantum spaces different from quantum planes and tori.

Within more standard quantum field theory and lattice gauge theories, there was a good deal of activity in the study of chiral lattice fermions, with a detailed study of various proposals and the analysis of chiral gauge theories on the lattice. Until recently it was not possible, even theoretically, to study gauge theories with chiral representations of matter (like the Standard Model) on the lattice. Several breakthroughs have taken place in recent years, and although we still have a long way to go, substantial progress has been accomplished in this field which is likely to be part of the Division’s activity in the years to come. There was also a continued study of lattice hadron matrix elements needed in the computation of non-leptonic weak processes, of the computation of effective chiral Lagrangians from the lattice, centre vortices and ’t Hooft loops; new studies of the properties of the non-perturbative QCD vacuum, and a long etcetera.

As in previous years, we had in the year 2000 a rather healthy activity in the subject of astrophysics and cosmology. Inflationary-type scenarios were explored in a wide variety of models, from brane cosmology to models inspired by the heterotic string, to Pre-Big-Bang cosmology. There were also studies of the cosmological implications of a low reheating-temperature after inflation, and there was interesting work in the area of entropy bounds and holography in the cosmological context. The increasing amount of data in these areas calls for refinements of existing models or the constructions of new ones. Different analyses to explain the anisotropies of the CMBR data were proposed. Among them there is the so-called quintessence hypothesis, related to the fact that perhaps a viable explanation of the dark matter is provided by the existence of a very small cosmological constant, something which seems to be suggested by recent astronomical

2 Theoretical Physics Division observations. The subject is far from being uncontroversial (both at the experimental and theoretical level) and it is actively being investigated both in the Division and elsewhere. Within more astrophysical subjects, models were proposed to explain the properties of gamma ray bursts, and new equations of state for supernovae. An intersecting, and somewhat controversial subject straddled between astrophysics and heavy- ion physics is the possibility of producing strangelets in RHIC and later on, in ALICE. Limits from experiments on cosmic rays and astrophysical observations were discussed.

There was a good level of activity in the field of heavy-ion physics and in the study of the quark–gluon plasma and of the distinctive signatures that may indicate its presence. New original work on the propagation properties of hard quarks and gluons in the nuclear medium was performed, and studies of transport properties of the plasma, together with the refinement of the analysis of the more standard signatures like strangeness enhancement and J/ψ-suppression continued. There was also some interesting work on the novel theories of colour superconductivity and several possible colourful transitions in dense hadronic matter, and on the study of weakly coupled quark–gluon plasmas.

As in previous years, the Division took responsibility for the organization of various international Workshops and meetings. The Theoretical Physics Division had a major role in the organization of the SUSY2K Conference, a major annual world event, which took place at CERN in June 2000. The Conference was a big success and, with a modest financial investment, contributed much to the image of CERN in the community. The Workshop on Standard Model Physics and More at the LHC was completed and the Proceedings appeared in spring 2000. A Workshop on Precision Calculations for LEP2 Physics was held over several months at CERN with a substancial participation of the Division. The Proceedings of the Workshop are available as CERN Report 2000–009. An active Workshop on Heavy-Ion Physics was also held at CERN and brought together from all over the world theorists and experimentalists working in the field. The Division is currently contributing very much to the ongoing study groups at CERN and elsewhere on future facilities like the linear collider and the neutrino factory. In the case of the ECFA-sponsored study for a neutrino factory, which took place at CERN throughout 2000, several members of the Division are actively working on the preparation of the final report, including contributions to the prospects for rare kaon decays, stopped-muon physics, deep-inelastic neutrino scattering, physics at the muon collider, as well as neutrino oscillations.

Theoretical Physics Division 3

Experimental Physics Division

The LEP Programme

ALEPH

The year 2000 was a truly exciting year for the ALEPH Collaboration (Annecy, Barcelona Auton. Univ., Bari, Beijing, CERN, Clermont-Ferrand, Copenhagen, Demokritos, Palaiseau Ecole Polytechnique, INFN Florence, INFN Frascati, Glasgow, Heidelberg, Imperial College, Innsbruck, Lancaster, Mainz, Marseille, INFN Milan, MPI-Munich, Orsay, INFN Pisa, RAL, Royal Holloway College, Saclay, Santa Cruz, Sheffield, Siegen, INFN Trieste, Washington, Wisconsin).

− For the last year of its operation the ALEPH detector collected 218 pb 1 data at centre-of-mass energies between 200 and 209 GeV, surpassing all expectations, thanks to the great performance of the LEP collider. ALEPH’s data taking efficiency was also a record, averaging about 95.8%. There was only one important problem during data taking, a short that developed in the main tracking chamber, which affected about one month’s data. For those data affected, appropriate corrections were established and the reprocessing took place within a few weeks. The final reprocessing of all data was completed before the end of the year.

High-energy data were of special interest for the searches, as with every energy increase a new unknown regime opens up. Being able to perform the analyses fast is very important; actually, since 1999, searches have been performed quasi-online. The high online quality of the data greatly facilitated this. This year’s analyses showed some intriguing evidence for the long-searched-for Higgs particle.

At the same time, the analysis of the 2000 data contributed significantly to precision electroweak measurements. In particular the measurement of the W boson mass, one of the most important parameters of the Standard Model, reached the impressive accuracy of 0.06%. Di-fermion production and QCD studies were also performed at centre-of-mass energies 200–209 GeV.

Finally, important results from the b-sector were produced this year from ongoing analyses of data taken during the LEP1 phase.

Overall, 22 papers were published or submitted for publication by ALEPH during 2000.

Experimental Physics Division 5 Searches

Before the 2000 data-taking period the LEP combined limit for the Standard Model Higgs boson mass was 113 GeV/c2. In the 2000 data a 3σ excess beyond the background expectation, peaking near 114.3 GeV/c2, was observed in ALEPH. This excess is illustrated in Fig. ALEPH–1 where the log-likelihood estimator –2lnQ is shown as a function of the Higgs mass for the observation (solid) and for background-only expectation (dashed). The signal hypothesis is also indicated (dash-dotted). Much of this excess was seen in the four-jet topologies where three high-purity events were found. Figure ALEPH–2 shows the event display of one such candidate with a reconstructed mass of 114.3 GeV/c2. Secondary vertices are clearly reconstructed in two of the jets, indicating the presence of b-quarks, the most likely decay products of a light Higgs. These exciting results were published very shortly after the LEP closure, in November 2000, leaving a legacy for future experiments to confirm or not.

The Higgs boson is also a major feature of the main extension of the Standard Model, the MSSM. In this there are five Higgs states and the lightest neutral one, h, should have a mass less than ~140 GeV/c2. In this scenario h is produced either in association with a Z boson as for the Standard Model or, depending upon the MSSM parameter tanβ, in association with the A, a CP-odd Higgs boson. No evidence for either process was 2 2 found and limits have been set at 91.2 GeV/c for mh and 91.6 GeV/c for mA. For standard values of supersymmetry parameters and a top mass of 175 GeV/c2 certain values of tanβ can also be eliminated: the excluded range is 0.7 to 2.1.

Supersymmetry has many facets and there has been a wide-ranging investigation of many of these. No evidence for any signal was observed and the negative results of the searches were translated into exclusion domains in the space of the relevant parameters. In the most popular scenario, R parity is conserved and the neutralino is the Lightest Supersymmetric Particle (LSP). Limits have been produced for the masses of the lightest chargino, the charged sleptons, the stop and the sbottom squarks as well as the charged Higgs; most results approached the kinematic limit. The limit for the invisible lightest neutralino requires analyses involving decays to the LSP. From these, a lower limit on the mass of the lightest neutralino, independent of the MSSM parameters, of 39.6 GeV/c2 was obtained. Other supersymmetry scenarios that have been investigated concern models without R-parity conservation, and those in which supersymmetry breaking is gauge mediated (GMSB). No evidence for such processes was observed.

Precision Measurements at LEP2

− Using all of the data collected above the WW production threshold since 1996, 710 pb 1 in total, measurements of the W boson properties reached significant precision.

The WW cross-section measurements, with a precision of below 1%, are shown in Fig. ALEPH–3 as a function of the centre-of-mass energy. They are in very good agreement with the most recent theoretical predictions (indicated by the line) including complete O(α) calculations.

Measurements of the triple gauge couplings involving a W boson set limits on deviations from the Standard Model via anomalous contributions to below 8% and 14%, for CP-conserving and CP-violating terms, respectively.

6 Experimental Physics Division The W mass was measured by direct reconstruction with the 2000 data using the semileptonic and hadronic channels and the results were combined with previous ALEPH measurements. The inclusion of the new data brought the statistical and systematic components of the measurement’s error to comparable levels. In anticipation of this, most efforts were concentrated on the understanding and controlling of systematic effects. The most significant sources of such effects were related to the simulation of the hadronic jet structure and the detector response. ALEPH’s preliminary average for the W Mass is 80.471 ± 0.049 GeV/c2, the most precise result coming from a single experiment, in good agreement with the value coming from the hadron colliders of 80.452 ± 0.062 GeV/c2.

Measurements of di-fermion pair properties were also performed, using all ALEPH data. The precision of the measured qq(γ) and Bhabha cross-sections reached a level comparable to the accuracy of the Standard Model predictions. The production cross-section and asymmetry are sensitive to many possible signs of new physics. Within uncertainties, measurements and predictions agree well and hence show no evidence for any new interactions.

Precision Measurements at LEP1

The analysis of LEP1 data also continued last year, with special emphasis on topics that could take advantage of the reprocessing of the four million Z decays in 1998. The main improvements concerned track reconstruction and particle identification. New analyses in the neutral B system have become possible, as well as more accurate repeats of previous work. Two of the most important results produced last year were a limit 2θ on the Bs oscillations frequency and a very precise determination of sin eff from the measurement of the forward–backward asymmetry in Z → bb decays.

∆ The determination of the Bs oscillations frequency ms is one of the major issues in the study of flavour dynamics. So far no experiment has directly observed oscillations, so only lower limits have been set. During 2000 three ALEPH analyses were presented, with significant impact on the world average limit. Two analyses used exclusively reconstructed Bs decays, one in totally hadronic final states and one in Ds plus lepton states. The first was new in ALEPH while the second had 20% better selection efficiency than the previously published analysis. The third analysis used inclusive semileptonic decays and was also an improvement on a previous analysis. Better vertex reconstruction and event selection, together with a better initial and final-state flavour tagging yielded a factor of 2 improvement in the measured amplitude sensitivity for high-frequency − oscillations. The sensitivity of this analysis is expected to be 11.9 ps 1. Figure ALEPH–4 shows the ∆ preliminary ALEPH combination of the measured amplitude, as a function of ms. The shaded band shows − the one-sided 95% confidence level contour. The combined expected sensitivity is 13.1 ps 1 while the −1 ∆ −1 measured 95% CL limit is 10.7 ps . The likelihood profile shows a minimum for ms = 17.3 ps , with a significance of just over two standard deviations.

An upgraded measurement of the forward–backward asymmetry AFB (b) was also performed using inclusive B decays. A Neural Net was employed, giving 30% increase in the selection efficiency compared to the previous ALEPH analysis. The b-flavour identification was based on the hemisphere-charge method but also included information from fast kaon tagging and vertex (primary and secondary) charge estimators. An overall 20% increase in sensitivity and a halving of the systematic error were achieved. The derived asymmetry value is AFB (b) = 0.1004 ± 0.0033 and the corresponding weak mixing angle 2θ sin eff = 0.23201 ± 0.00058.

Experimental Physics Division 7 ALEPH Dismantling

In December 2000, after 10 years of successful operation and a plethora of interesting results, the dismantling of ALEPH started. However, the ALEPH Collaboration remains active and physics analyses will continue as there are still significant results to finalize and improvements to be made.

20 2 ln Q 2 ln

− 15

−5

−10

−15

−20 106 108 110 112 114 116 118 120

2 mH(GeV/ c )

Fig. ALEPH–1: The log-likelihood estimator as a function of the Higgs boson mass for the observation (solid) and background-only expectation (dashed).

DALI_F1 ECM=206.7 Pch=83.0 Efl=194. Ewi=124. Eha=35.9 BEHOLD Run=54698 Evt=4881 ALEPH Nch=28 EV1=0 EV2=0 EV3=0 ThT=0 000614 2:32 Detb= E3FFFF 5 Gev EC (φ -138)*SIN(θ) 5 Gev HC o

o o x x o - -

- o ox xo-o o ox ooox o x x - - x o-oxo o

o o o o o o x xx- o - x o x - x - - - o - o 0.6cm o o o o x Y"

µ 0.3cm 15 GeV x 1cm 0 1cm X" P>.50 Z0<10 D0<2 F.C. imp. θ=180 θ=0 RO TPC

Fig. ALEPH–2: Four-jet candidate with two highly b-tagged jets and a Higgs boson mass of 114.3 GeV/c2.

8 Experimental Physics Division 20

RacoonWW / YFSWW 1.14 17.5

12.5 WW Cross Section (pb)

7.5 18 YFSWW1.14 RacoonWW 5 17

2.5 16

0 160 170 180 190 200 210

Ecm(GeV) Fig. ALEPH–3: Measurements of the WW cross-section at ten centre-of-mass energies compared with the Standard Model predictions.

3.5 data ± 1 σ 95% CL limit 10.7 ps-1 1.645 σ sensitivity 13.1 ps-1 Amplitude 3 data ± 1.645 σ 2.5 data ± 1.645 σ (stat only)

1.5

0.5

−0.5

−1 0 2 4 6 8 101214161820 ∆ −1 ms (ps ) ∆ Fig. ALEPH–4: Bs oscillations amplitude as a function of ms.

Experimental Physics Division 9 DELPHI

The DELPHI Collaboration (Ames, Amsterdam, Antwerp, Athens, Bergen, Bologna, Bratislava, Brussels, CERN, Cracow, Dubna, Genoa, Grenoble, Helsinki, Karlsruhe, Lisbon, Liverpool, Ljubljana, Lund, Lyon, Marseille, Milan, Mons, Orsay, Oslo, Oxford, Padua, Paris, Prague, Rio de Janeiro, Rome, Rutherford, Saclay, Santander, Serpukhov, Stockholm, Strasbourg, Torino, Trieste, Udine, Uppsala, Valencia, Vienna, Warsaw, Wuppertal) resumed detector operation again mid-March 2000, with first beams from LEP on 3 April.

During the year DELPHI recorded data with an average efficiency of 95.3% at centre-of-mass energies − − between 202 and 209 GeV. The total integrated luminosity corresponded to 226 pb 1, of which 8.6 pb 1 was − collected at the highest energy around 208 GeV. An additional 4.0 pb 1 of data collected at 91 GeV was used for calibrating the detector.

Only minor repairs were needed during the shutdown. This minimal perturbation of the detector allowed a fast alignment and calibration to be made using the Z data taken in April, providing high-quality data for the results presented at ICHEP2000 in Osaka and at the three LEPC presentations in September, October and November.

Owing to a slack sense wire in one of the TPC sectors, on several occasions a new HV working point was needed for this sector to prevent it from tripping. Since 1 September this sector (1/12 of the TPC acceptance) was completely off. The effect on the overall tracking efficiency was limited due to the redundancy in the tracking provided by the Vertex, Inner and Outer detectors and was taken into account in the physics results by producing simulation samples with this TPC sector off.

Physics Highlights

DELPHI published 33 papers in refereed journals in 2000, 17 papers still being based on LEP1 data.

Sixty-two papers were submitted to ICHEP2000 in Osaka (Japan), of which 16 were based exclusively on LEP1 data and 46 based on LEP2 data, including results from the 2000 run.

The LEP1 results can be grouped as follows: nine papers on heavy quarks, four on QCD and 2-photon physics, two on τ leptons and one on the Z line-shape.

Highlights of the LEP1 results published in journals or presented in Osaka:

– Final results on the cross-sections and leptonic forward–backward asymmetries from the Z running of LEP (see Fig. DELPHI–1).

– Almost-final measurement of the b quark forward–backward asymmetry at the Z peak.

– Final results on the Michel parameters and the average ντ helicity in τ decays, together with the first measurement of the tensor coupling in the weak charged current.

0 − 0 – A combination of five different analyses on Bs Bs oscillations yielded a limit on the mass difference 0 ∆ −1 between the physical Bs states of ms > 7.3 ps at 95% CL, where the sensitivity of this combined − analysis is 10.6 ps 1.

10 Experimental Physics Division – An improved determination of the b-quark mass, from the measured normalized ratio of the three-jet rate for b-quark and light (uds) quark events, compared to the theoretical predictions including NLO radiative corrections with mass effects.

More τ results (topological branching ratios, multiprong τ decays into kaons and a much improved measurement of the τ lifetime) were presented at the TAU2000 conference in Victoria BC (Canada).

The LEP2 results presented in Osaka can be grouped as 28 papers on searches for new phenomena, 8 on W-pairs and other four-fermion final states, 4 on QCD and 2-photon physics, and 6 on fermion-pair and γ-pair − studies. The 96 pb 1 of data taken at energies between 203 and 208 GeV before Osaka were used to update the 2 searches for neutral Higgs bosons, giving in the Standard Model framework a lower limit mH > 109.0 GeV/c 2 2 at 95% CL and in the MSSM framework mh > 85.1 GeV/c and mA > 86.7 GeV/c . In addition, the searches for Higgs bosons decaying into invisible particles, for charged Higgs bosons, for supersymmetric particles, and for more exotic states (fermiophobic Higgs, excited leptons and technicolour production) were updated. A few unique searches were done by DELPHI:

– A search was made for the supersymmetric partner of the goldstino, the sgoldstino S in the production channel Sγ followed by the decay of S into two gluons or two photons. No excess of events and no clear evidence of anomolous production of events with monochromatic photons were observed.

– In some supersymmetric models the gluino could be the Lightest Supersymmetric Particle (LSP). It would hadronize to form R-hadrons (both charged and neutral). A search has been made for R-hadrons ˜ in the decay of the lightest stop t1 → cg˜ . Charged R-hadrons are identified through anomolous ionizing energy loss in the tracking detectors while for neutral R-hadrons an interaction model is used to estimate the average energy loss in the calorimeters. No deviation from Standard Model predictions was seen and exclusion regions in the plane (m~ , m~ ) were derived. t1 g

Although the three subsequent LEPC meetings in September, October and shortly after the end of data taking in November were mainly devoted to the presentation of updated results from new particle searches, many new (preliminary) results on Standard Model measurements were obtained as well. These include results on fermion-pair production cross-sections, forward–backward asymmetries and Rb at LEP2 energies, from which e.g. limits on the scale of contact interactions can be set at values between 5 and 15 TeV, depending on the helicities of the fermionic currents involved, and lower limits on the mass of an additional neutral gauge boson Z´ between 300 and 500 GeV/c2, depending on the model chosen. The measurements of the W mass and the trilinear gauge boson couplings using data up to 202 GeV were presented in Osaka. The ∗ W-pair and Z-pair production cross-section measurements (Fig. DELPHI–2) and also single-resonant Zγ with in particular the ννqq (‘monojet’) production (Fig. DELPHI–3) were later complemented with the full 2000 statistics.

Just before the end of the year, a paper on the search for the Standard Model Higgs boson, based on all data collected in 2000 and before, was submitted for publication. The search was performed in the channels Hνν, + − + − + − He e , Hµ µ , τ τ qq and in the four-jet channel. The missing energy channel and the four-jet channel were better optimized for a high-mass Higgs. The data for all channels is compatible with the expectations from the Standard Model background and a lower limit on the mass of the Standard Model Higgs boson of 2 114.3 GeV/c was set. In Fig. DELPHI–4 the test-statistic is plotted as a function of mH, from which it can be

Experimental Physics Division 11 derived that the DELPHI result has a 3% probability to be consistent with the presence of a Higgs of mass 115 GeV/c2.

40 FB 0.3 µ+µ−

1990 A (nb) 0.2

σ 1991 1992 0.1 1993 0 20 1994 1995 −0.1 1990 −0.2 1991 1994 1992 −0.3 1995 1993 0 −0.4 87 88 89 90 91 92 93 94 95 96 87 88 89 90 91 92 93 94 95 96 √s (GeV) √s (GeV) 0.4 0.05 (nb)

(fit)

fit 0.04

FB 0.03 A − σ

− 0.02

meas 0.01 σ 0 0 −0.01 (meas)

FB −0.02 A −0.03 −0.04 − 0.4 −0.05 87 88 89 90 91 92 93 94 95 96 87 88 89 90 91 92 93 94 95 96 √ s (GeV) √s (GeV)

Fig. DELPHI–1: Left: Hadronic cross-sections from 1990–95 data. Right: Forward–backward asymmetries in the µ+µ− channel. The lower plots show the differences between the measured points and the best fit values; for clarity only the 1992–95 data are shown. The curves represent the results of a 5- parameter fit to the cross-section and asymmetry data.

20 PRELIMINARY

17.5 YFSWW and RacoonWW 1.5 Published results from 15 1997 and 1998 data PRELIMINARY results from 1999 and 2000 data 12.5 19 1

WW Cross Section (pb) 18.5 10 18

7.5 17.5 0.5

5 NC02 Cross-Section (pb) 16.5 0 16 170 180 190 200 210 2.5 CMS Energy (GeV) 15.5 190 192 194 196 198 200 202 204 206 208 210 0 160 170 180 190 200 210 √s (GeV)

+ − Fig. DELPHI–2: Left: measurements of the W W cross-section compared with the Standard Model prediction. The shaded band represents the theoretical uncertainly. Right: the Z-pair production cross-section compared with the Standard Model prediction.

12 Experimental Physics Division Fig. DELPHI–3: The distribution of the mass of the hadronic system in the νν qq selection. The darker shaded histogram shows the expected signal contribution.

25 0.2 20 0.18

-2 ln(Q) 0.16 15 0.14 10 0.12 0.1 5 0.08 Probability density 0.06 0 Observed 0.04 m =115.0 -5 Expected background H 0.02 Expected signal + background 0 -10 -20 -15 -10 -5 0 5 10 100 102 104 106 108 110 112 114 116 118 120 2 -2lnQ(115) mH(GeV/c )

Fig. DELPHI–4: Left: the test-statistic (negative log-likelihood ratio) as a

function of mH. The observed value, full line, is compared to the expectation for the background-only hypothesis, represented by the dashed line and the symmetric 68% and 95% probability shaded bands. The dot-dashed line shows the average expected result for a hypothetical Higgs mass of 115 GeV/c2. Right: vertical slice of the previous plot for a mass value of 115 GeV/c2, showing the sensitivity of the DELPHI result to this hypothesis. The dot-dashed line shows the expected distribution for signal plus background, the dashed line that for background only. The vertical line represents the data.

Experimental Physics Division 13 L3

L3 is a collaboration of institutes from Aachen (RWTH), Amsterdam (NIKHEF and Amsterdam), Ann Arbor (Michigan), Annecy (LAPP), Basel, Baton Rouge (Louisiana State), Beijing (IHEP), Berlin (Humbold), Bologna (INFN), Bombay (Tata), Boston (Northeastern), Bucharest, Budapest, Cambridge (MIT), CERN, Florence (INFN), Geneva, Hamburg, Hefei, Helsinki (SEFT), Lausanne, Lecce (INFN), Los Alamos, Lyon (IPN), Madrid (CIEMAT), Milano (INFN), Moscow (ITEP), Naples (INFN), Nicosia (Cyprus), Nijmegen, Pasadena (Caltech), Perugia (INFN), Pittsburgh (Carnegie Mellon), Princeton, Rome (INFN), St. Petersburg (NPI), Salerno (INFN), San Diego (UCSD), Santiago de Compostella, Sofia, Taegu, Taiwan, Tuscaloosa (Alabama), Utrecht, Villigen (PSI), West Lafayette (Purdue), World Laboratory, Zeuthen (DESY) and Zürich (ETH).

The L3 experiment is designed as a general-purpose detection system with emphasis on the measurement + − of electrons, photons, muons and jets produced in e e interactions with good spatial and energy resolution. During the year 2000 LEP attained its maximum beam energy and delivered the highest integrated luminosity − of its 11 years of running. The following luminosities were recorded by L3: 78.9 pb 1 at s = 204.8 GeV, − − 130.1 pb 1 at s = 206.5 GeV, and 8.7 pb 1 at s = 208.2 GeV.

In the year 2000, 25 papers were published in Physics Letters and 2 in the European Physical Journal. Furthermore the L3 Collaboration contributed 58 papers to the ICHEP2000 Conference in Osaka (Japan). Members of the collaboration gave 40 talks at conferences and workshops.

The main goal of the year 2000 LEP running was the search for the Higgs boson and supersymmetric particles. The cross-section for the production of a Standard Model Higgs of 114 GeV mass in the reaction + − + − e e → ZH is compared in Fig. L3–1(left) to hadronic production in various e e channels. For the Higgs + − search the main backrounds are the annihilation e e → qq(γ) channel, and W or Z pair production. In Fig. L3–1 (right) a candidate Higgs event is shown. This event presents two nearly back-to-back jets with a large amount of missing energy and very little missing momentum, compatible with the production of the Higgs, decaying into two jets, and the Z nearly at rest. Both jets have a clear secondary vertex, indicating the presence of a b-quark. By assuming a Z →νν decay, a kinematical fit gives a mass of 114 GeV for the Higgs, with a resolution of about 3 GeV. The main sources of spelling for this event are double radiative production of an off-shell Z and Z-pair production. Preliminary results of the Standard Model Higgs analysis of the year 2000 data were published in Physics Letters at the end of the data taking.

Supersymmetric particles were searched for in many different channels and kinematical regions. No signal was observed and in many channels limits corresponding to the allowed kinematic phase space could be established. Two examples are given in Fig. L3–2 for the chargino mass limits. By exploiting the complementarity of the different searches, an absolute limit on the mass of the lightest supersymmetric particle has been set at 39.2 GeV.

+ − + − A significant excess is observed at 68 GeV in four-jet events, in the analysis of the e e → H H channel, ± with H → cs, τν. The significance of this excess, already observed in the previous high-energy data, increases with the luminosity of the year 2000 data. The mass spectrum obtained by a kinematical fit, with an equal mass constraint, after the subtraction of the Standard Model backgound, is shown in Fig. L3–3. It has a

14 Experimental Physics Division significance of 4.4 standard deviations, about one standard deviation below the expected cross section for charged Higgs production.

One of the main goals of the LEP programme was the measurement of the the W and Z boson properties. The cross-sections for the pair production of W and Z bosons is shown in Fig. L3–4. Good agreement with the Standard Model calculations is observed, excluding models not containing triple-gauge-boson couplings. Events with Z bosons decaying into b-quarks are also singled out and the agreement of their production cross- section with the Standard Model predictions validates the detector’s capability to observe a similar configuration in the search for the Higgs boson.

The fermion-pair production cross-sections and leptonic forward–backward asymmetries were measured. The results are in good agreement with the Standard Model predictions. The high-energy data allow the measurement of the γ−Z interference term and a determination of the Z mass in an S-matrix approach. In Fig. L3–5 (left) the improvement of the present measurement is evident, compared to the results obtained at ± ± LEP1. The Z mass value thus obtained, MZ = 91188.4 3.1 (stat.) 1.8 (syst.) MeV, reaches the same ± precision as the value MZ = 91189.5 3.1 MeV obtained from a Standard Model 5-parameter fit.

α Precise QCD studies have continued with the determination of the strong coupling constant s up to 208 GeV. The results, shown in Fig. L3–5 (right), are obtained from the measurement of event shape variables. The studies of Bose–Einstein correlations and colour reconnection effects in W-pair events are now of primary importance for a precise determination of the W mass and detailed analyses of those effects are continuing within L3.

Perturbative and non-perturbative QCD is also studied in two-photon interactions. The cross-section of γγ → hadrons as a function of the two-photon centre-of-mass energy, Wγγ, shows an early onset of QCD processes due to the γ→qq quantum fluctuation. This is evident in the γγ → cc cross-section, compared in Fig. L3–6 (left) to the total hadronic cross-section. Here the hard scattering dominates and the γ–gluon fusion diagram plays an important role. This measurement provides clear proof of the existence of a gluon component inside the photon. The cross-section for b production was measured in γγ collisions for the first time; it is in excess of the QCD predictions by a factor of three. The transition between soft interactions, represented by Vector Dominance Models, and QCD hard scattering is well demonstrated by the pt dependence of the inclusive production of π0 in hadronic two-photon events, as illustrated in Fig. L3–6 (right).

Experimental Physics Division 15 most significantHνν candidate

10 e+e– → e+e–hadrons Wγγ > 5 GeV

-1 10 s' / s > 0.85 _ ] e+e– → γ/Z → qq(γ) nb [

σ -2 Secondary vtx’s view 10 + – + − e e → W_ W_ mass=5.5 GeV → qqqq -3 7.3mm to prim. vtx 10

mH=114 GeV 1.4mm to prim. vtx _ _ + – + – -4 e e → HZ → qqqq e e → ZZ_ _ 10 → qqqq 80 100 120 140 160 180 200 220 s [GeV]

+ − Fig. L3–1: Left: Cross-sections for hadron production in e e collisions as a function of the centre-of-mass energy, s , for different processes. The Standard Model predictions are superimposed to the data. Right: The L3 Higgs candidate, + − e e → HZ → H.νν

120 tan β = 2 L3 115 µ = -200 GeV Preliminary (GeV) 1 + ~ χ

M 110 χ~+> higgsino CMSSM M 1 103.2 standard 105

100 ~ Mχ+>98.6 1 ISR 85.9 GeV 1 95 -1 M (GeV) LEP I 90

∆ 10 stable 85 Excluded at 95 % C.L. -2 L3 preliminary 10 80 40 60 80 100 50 100 150 200 250 300 350 ~ χ+ M~ (GeV) M 1 (GeV) ν

Fig. L3–2: Left: Mass limits for a CMSSM higgsino, independent of the mass difference to the lightest supersymmetric particle, ∆M. Right: Chargino mass limits as a function of the neutralino mass.

16 Experimental Physics Division 1 Data−Background 100 -1 √s = 183−209 GeV 10 − __ _ −_ H+H → cscs and csτ ν : -2 τ 10 MH = 68 GeV 3σ -3 10

50 b -4 CL 4σ

− 10 1 -5 4.4σ 10 Signal

0 -6 MH = 68 GeV 10 5σ Difference of events / 2 GeV of events Difference -7 Observed ±1σ band 10 Expected ±2σ band

40 60 80 100 60 70 80 [ ] ± [ ] Mass GeV MH GeV

+ − + − Fig. L3–3: The reaction e e → H Η . Left: The mass distribution of the events obtained after a 5C kinematical fit and the Standard Model background subtraction. Right: The statistical significance of the peak at 68 GeV.

√s ≥ 192 GeV: preliminary 2 ZZ Data + − ] e e →ZZ 20 pb ZZ→bbX Data [ + − 1.5 e e →ZZ→bbX )) γ ( − W

+ 1

W 10 →

− Data e + YFSWW3 0.5 Cross Section (pb) (e

σ RACOONWW

0 0 160 170 180 190 200 210 170 180 190 200 210 √s [GeV] √s (GeV)

Fig. L3–4: The cross-section for (left) W-pair and (right) Z-pair production as a function ofs .

Experimental Physics Division 17

1.5 68% CL 5-par fit

0.17 Reduced √s 0.5 √s =91.2 GeV 0.16 LEP 1.5 LEP 2 tot had j SM 0.15 QCD Evolution α Constant s 0.14

0 s 0.13 α

0.12

0.11 -0.5 L3 Z data L3 all data 0.1

0.09 20 40 60 80 100 120 140 160 180 200 220 91.17 91.18 91.19 91.2 [ ] √s (GeV) mZ GeV tot − Fig. L3–5: Left: Contours in the jhad mZ plane at 68% confidence level. The dashed line is obtained from Z data only, while the solid line includes the high- tot energy data. The Standard Model prediction for jhad is shown as the horizontal band. The vertical band corresponds to the 68% confidence level interval on the Z mass, from a fit assuming the Standard Model value for the γ−Z interference. α Right: The running of s, measured with all L3 data.

4 800 10 Regge fit to the data → π0 3 ee ee +X Universal parameters 10 Exponential fit 2 600 ] 10 Power law fit γγ → hadrons

] 10 nb [ pb / GeV

[ γγ 400 t 1 σ

/ dp -1

σ 10 d 200 γγ → -2 ( ccX) x 4 10

-3 10 0 50 100 150 5101520 [ ] [ ] Wγγ GeV pt GeV Fig. L3–6: Left: The cross sections for γγ → hadrons and γγ → ccX as a function of the two-photon centre-of-mass energy, Wγγ.. Right: The differential cross- section for the inclusive production of π0 as a function of the π0 transverse momentum in two-photon interactions.

18 Experimental Physics Division OPAL

The OPAL Collaboration consists of groups from Aachen, Alberta, Birmingham, Bologna, Bonn, RMKI- KFKI Budapest, Cambridge, Carleton, CERN, Chicago, ATOMKI Debrecen, DESY/Univ. Hamburg, Freiburg, Heidelberg, Indiana, Kobe, Queen Mary and Westfield College London, University College London, Manchester, Maryland, Montréal, LMU München, MPI München, Oregon, CRPP-Ottawa, Rutherford Appleton Laboratory, Technion, Tel Aviv, Tokyo, Victoria, UBC Vancouver, UC Riverside, Weizmann Institute and Yale.

+ − The general-purpose OPAL detector at the LEP e e storage ring is used for a wide range of physics studies. After more than eleven years of successful data taking starting 13 August 1989, operation of LEP and the OPAL detector was finally terminated on 2 November 2000. No major detector failures have occurred throughout the entire operation: All 9440 channels of the electromagnetic barrel calorimeter were still fully functional, and not a single wire of the central Jet Chamber, out of a total of 19 776 wires, ever broke.

− In the final running year 2000, an integrated luminosity of 219.2 pb 1 at centre-of-mass energies of 200– 209 GeV was collected, with an average data-taking efficiency above 92%. Since 1989, a total integrated − − luminosity of 900 pb 1 was collected, with an overall efficiency of 90%, where 700 pb 1 were recorded at + − energies above the W W threshold.

Heavy Flavour Physics

Heavy flavour physics still continues to be a rich field of studies. Production rates have been measured for gluon splitting to bb quark pairs, gbb, and of events containing two bb quark pairs, g4b, using a sample of four- jet events. Information from the event topology was combined in a likelihood fit to extract the values of gbb φ and g4b. For the first time, the inclusive production rate of mesons from the decay of b hadrons produced in Z decays was measured, and found to be Br(b →φX) = 0.0282 ± 0.0013 (stat.) ± 0.0019 (syst.). At centre-of- σ + − → σ + − → mass energies up to 189 GeV the cross-section ratio Rb = (e e bb)/ (e e qq´) and the bottom and b c charm forward–backward asymmetries AFB and AFB were measured.

0 ∗+ − 0 B → D l ν decays were used to measure the lifetime and oscillation frequency of the B and the magnitude of the Cabibbo–Kobayashi–Maskawa matrix element Vcb. The product of Vcb and the decay form 0 ∗+ − factor of the B → D l ν transition at zero recoil F1 was measured to be =(37.1±1.0±2.0)× −3 F(1) Vcb 10 , where the uncertainties are statistical and systematic respectively. This 0 − + is the best measurement by a single experiment. A sample of Bs decays was obtained using D sl − φ −ν combinations. The D s was fully or partially reconstructed in the l X decay channel. These events were used 0 to study Bs oscillation and new limits on the oscillation frequency were deduced.

Tau Physics

The mass of the τ was measured to be 1775.1 ± 1.6 (stat.) ± 1.0 (syst.) MeV using τ from Z decays (Fig. OPAL–1). In order to test CPT invariance, the masses of the positively and negatively charged τ leptons − were compared. The relative mass difference was found to be smaller than 3.0 × 10 3 at the 90% confidence level.

Experimental Physics Division 19 QCD Studies and Inclusive Particle Production

In an integrated QCD study, data taken by JADE and OPAL at centre-of-mass energies ranging from 35 GeV through 189 GeV were used to determine the strong coupling strength (Fig. OPAL–2). The study was based on four jet-multiplicity related observables with the JADE, Durham, Cambridge and cone jet finders.

ξ ξ The mean charged particle multiplicity 〈nch〉 and the peak position 0 in the p = ln(1/xp)distribution was measured up to s = 189 GeV and, separately, for the three light quark flavours around s = 91.2 GeV. Events from primary u, d, and s quarks were tagged by selecting characteristic particles which carry a large fraction of the beam energy. The result is consistent with the flavour independence of the strong interaction. Adding tagged heavy quark events, the energy distribution and type of the particle with the highest momentum for each of the five quark flavours was determined, making only minimal model assumptions. The multiplicities of π0, η, K0 and of charged particles was compared in quark and gluon jets in 3-jet events. Ratios of particle multiplicities in gluon to quark jets were found to be independent of the particle species.

ρ ρ ± ω In a study of spin alignment, the helicity density matrix elements 00 of (770) and (782) mesons were measured and found to be compatible with 1/3, corresponding to a statistical mix of helicity −1, 0 and +1 states. Bose–Einstein correlations in pairs of identical charged pions were studied as a function of the three components of the momentum difference with respect to the thrust direction. The results indicated that the source of identical pions has an elongated shape.

Standard Model Physics and W Production

Using data samples up to s = 189 GeV, the production and characteristics of W bosons were extensively studied: the W-pair production cross-section was measured and, when combined with previous OPAL measurements, the W boson branching fraction to hadrons was determined to be 68.32 ± 0.61 (stat.) ± 0.28 (syst.)% assuming lepton universality. The mass and width of the W boson were directly measured (Fig. OPAL–3). The consistency of the direct measurements with that inferred from other measurements of electroweak parameters provides an important test of the Standard Model of electroweak interactions.

W ≡ Γ → The fundamental coupling of the charm quark to the W boson was studied. The ratio Rc (W cX)/ Γ(W → hadrons) was measured from jet properties, lifetime information, and leptons produced in charm decays. By combining this result with measurements of the W boson total width and hadronic branching ratio, the magnitude of the CKM matrix element Vcs was determined.

+ − + − + − Z boson pair production was studied in final states containing only leptons, (l l l l and l l ν ν), quark + − and lepton pairs, (qq l l , qq νν) and the all-hadronic final state (qq qq ). qq and bb final states were considered separately using lifetime and event-shape tags. Limits on anomalous ZZγ and ZZZ couplings were + − derived. The polarization of W W boson pairs and of CP-violating WWZ and WWγ trilinear gauge couplings was studied. The measurements were performed through a spin density matrix analysis of the W boson decay products. Trilinear couplings of the neutral gauge bosons were also searched for in the process + − e e → Zγ. All results are consistent with Standard Model expectations.

20 Experimental Physics Division Higgs and Other Searches

The search for the Standard Model Higgs boson was performed based on the full data sample collected at s ≈ 192–209 GeV in 1999 and 2000. A lower bound of 109.7 GeV was obtained on the Higgs boson mass at the 95% confidence level. At higher masses, the data are consistent with both the background and the signal-plus-background hypotheses (Fig. OPAL–4).

Searches for the neutral Higgs bosons h and A were used to obtain limits on the Type II Two Higgs Doublet Model (2HDM(II)). For the first time, the 2HDM(II) parameter space was explored in a detailed scan, and new flavour-independent analyses were applied. Searches for unstable neutral and charged heavy leptons, ± ∗ ∗ ∗ ∗ N and L , and for excited states of neutral and charged leptons, ν , e , µ , and τ , were performed. From the analysis of charged-current, neutral-current, and photonic decays of singly-produced excited leptons, upper limits were determined for the ratio of the coupling to the compositeness scale, f/Λ, for masses up to the kinematic limit. Searches for final states expected in models with light gravitinos were performed, including experimental topologies with multi-leptons with missing energy, leptons and photons with missing energy, and jets and photons with missing energy. The single-photon results were also used to place upper limits on superlight gravitino pair production as well as graviton–photon production in the context of theories with additional space dimensions.

Two-Photon Physics

The total hadronic cross-section for the interaction of real photons was measured for centre-of-mass energies 10 ≤ W ≤ 110 GeV and was compared with Regge factorization models and with the energy + − + − dependence observed in γp and pp interactions. The total cross-section for the process e e → e e cc was γ determined and a first measurement of the charm structure function F2c, of the photon was performed in the 2 2 2 γ 2 kinematic range 0.0014 < x < 0.87 and 5 GeV

Summary

In total, 330 papers over a wide range of topics have been published since 1989. Of the 30 papers which were published or have been accepted by journals in 2000, 14 covered LEP1 subjects and 16 reported results at higher energies. In addition, many OPAL results were presented at conferences throughout the year. At the ICHEP2000 conference in Osaka, OPAL contributed 105 papers. In total, 117 talks were given at international conferences. As in previous years, students contributed strongly both to the physics output and to the operation of the experiment, and 14 PhD theses were completed. The analysis of OPAL data will continue over the next years. Major results from various LEP2 searches are expected for 2001. Standard Model physics and related topics will be ongoing for a longer time. Currently, about 50 PhD students are working on the completion of their theses within the next few years.

Experimental Physics Division 21 80 70 60 50 Number of cones 40 30 20 10 0 1.4 1.5 1.6 1.7 1.8 1.9 m* [GeV] cn

* τ→ π±ν Fig. OPAL–1: The distribution of the pseudomass mcn from the 3 τ class. The points with error bars are data and the open histogram is the Monte Carlo prediction including the background from misidentified τ decays (shaded area) normalized to the data. The solid line shows the parametrization in the fit window (1.6 to 2.0 GeV) after the final unbinned maximum likelihood fit to the data. The events have been binned for the presentation only.

0.17 (Q)

s comb.

α 0.16 result

0.11 0.15 D C D C D2 D2 N N 0.14

0.1 0.13 188 190

0.12

0.11

0.1 α (M )=0.119±0.004 0.09 s Z 20 40 60 80 100 120 140 160 180 200 Q [GeV] α Fig. OPAL–2: The combined results for s(Q) (Q=s ) from fits of the matched predictions plotted versus the c.m.s. energy. Arranged around the combined values are the contributing separate results for each of the four observables under consideration. All results are shown with their total errors (outer error bars) and the purely experimental component of the errors (inner bars). A three- loop evolution of the current world average is overlaid as solid and dotted lines.

22 Experimental Physics Division OPAL √s=189 GeV

% 2.6 39 CL / GeV

W 86% CL Γ

2.4

2.2

1.8

OPAL data 1.6 Standard Model

80.2 80.3 80.4 80.5 80.6 80.7

MW / GeV

Fig. OPAL–3: The 39% and 86% contour levels of the two-parameter fit using the reweighting method including systematic contributions. The Standard Model Γ relation between MW and W is shown by the dashed line.

0.25 OPAL Observation -2lnQ 20 0.2 Background Only Signal+Background 0.15 m = 115 GeV 10 H

0.1 d(Probability)/d(-2lnQ) 0 Observed 0.05 Exp. Backg Exp. Sig+Backg -10 0 100 105 110 115 120 -20 -15 -10 -5 0 5 10 mH (GeV) -2lnQ

Fig. OPAL–4: Left: The log-likelihood ratio −2 lnQ comparing the relative consistency of the data with the signal+background hypothesis and the

background-only hypothesis, as a function of the test mass mH. The observation for the data is shown with a solid line. The dashed line indicates the median background expectation and the dark (light) shaded band shows the 68% (95%) probability intervals centred on the median. The median expectation in the presence of a signal is shown with a dot-dashed line where the hypothesized signal mass is the test mass. Right: The −2 lnQ distribution expected in a large number of fictitious background-only experiments (solid histogram), and in a large number of fictitious experiments in the presence of a 115 GeV Higgs boson (dashed histogram). The observation in the data is shown with a vertical solid line.

Experimental Physics Division 23 The LHC Programme

ATLAS

Scientific Potential

ATLAS is a general-purpose experiment for recording proton–proton collisions at the LHC. The detector design has been optimized to cover the largest possible range of LHC physics: searches for Higgs bosons and alternative schemes for the spontaneous symmetry-breaking mechanism; searches for supersymmetric particles, new gauge bosons, leptoquarks, and quark and lepton compositeness indicating extensions to the Standard Model and new physics beyond it; studies of the origin of CP violation via high-precision measurements of CP-violating b-decays; high-precision measurements of the third quark family such as the 0 top-quark mass and decay properties, rare decays of b-hadrons, spectroscopy of rare b-hadrons, and Bs - mixing.

Overall Layout

The ATLAS detector, shown in Fig. ATLAS–1, includes an inner tracking detector inside a 2 T solenoid providing an axial field, electromagnetic and hadron calorimeters outside the solenoid and in the forward regions, and barrel and end-cap air-core-toroid muon spectrometers. The precision measurements for photons, electrons, muons, τ-leptons and b-quark jets are performed over η < 2.5 (muon spectroscopy extends to η < 2.7). The complete hadronic energy measurement extends over η < 4.8.

Fig. ATLAS–1: The ATLAS detector for the LHC.

Inner Tracking Detector

The inner tracking detector consists of straw drift tubes interleaved with transition radiators for robust pattern recognition and electron identification, and several layers of semiconductor strip and pixel detectors providing high-precision space points. The TRT straws have been produced and the straw reinforcement is up to speed in Russia. The tooling for straw module assembly is either ready or being finalized. The TRT barrel module production has started. The front-end electronics have been prototyped as radiation-hard circuits in the DMILL technology and the performance before and after irradiation has been verified in 2000. For the two

24 Experimental Physics Division silicon systems the two most central components are the silicon sensors and FE ASICs. The development and prototyping of silicon sensors is complete and the sensor preproduction and production are under way. Both systems’ designers are confident that their designs can handle the LHC operation conditions. The radiation- hard electronics prototypes for the SCT have been carefully evaluated in 2000 and built into barrel and forward SCT modules. The PIXEL readout electronics is being transferred to radiation-hard processes. The support structures, hybrids and cooling systems for both systems are at the stage of final prototyping. The SCT barrel-structure tender is out. The PIXEL installation scheme has changed in 2000 and the detailed designs of this scheme started at the end of the year.

Calorimeter

The electromagnetic calorimeter is a lead–LAr sampling calorimeter with a high-granularity first sampling for shower pointing and π0 rejection and a presampler layer immediately behind the cryostat wall for energy recovery. The end-cap hadronic calorimeters also use liquid-argon technology, with copper absorber plates. The end-cap cryostats house the electromagnetic, hadronic and forward calorimeters (tungsten–LAr sampling). The barrel hadronic calorimeter is an iron-scintillator sampling calorimeter with longitudinal tile geometry. In 2000 the various detectors of the LAr system have taken test beam data with either so-called module-0 or series modules. Despite small problems, including sometimes quality of the beam, the results are very satisfactory and compatible with Monte Carlo simulations. Results are prepared for publication. During 2000, HV hardness for the very forward calorimeter was achieved by continuation of a 1000-tube test, and material procurement for production was started. For the hadronic end-cap calorimeter the series production was restarted and about one quarter of all modules has been produced. Cold electronics is about halfway through production. For the electromagnetic calorimeter, module-0s have been assembled and evaluated in a test beam. The series production of the mechanics was continued and is fairly advanced. Full series production of the electrodes is now progressing. Flat electrodes are produced on a routine basis with good rate and efficiency. Final optimization for the bending process is on its way. A major step forward was made in the fabrication of the barrel and end-cap cryostats and in the final design and start-up of production of the cryogenic system. Most parts of the cryostats have been produced. Two of the three cryostats have successfully passed major tests. Production of the pin carriers is on its way, the assembly of feedthroughs has started in two places. Finally, the various parts of the electronics continued through a large number of design reviews and Production Readiness Reviews (PRRs). The ROD demonstrator project was successfully completed.

For the tile calorimeter the mass production of the mechanical wedges has continued. In 10 different plants, worldwide, identical submodules are being constructed. In three different plants these submodules are being assembled together in modules. During 2000 about 70% of the submodule production was achieved, as well as 45% of the mechanical-wedge production. In four different plants the modules are being instrumented with optical elements (1000 km of green optical fibres and 58 tons of scintillator plates). During 2000 about 90% of the scintillating-tile production was achieved, as well as more than 50% of plastic profiles with inserted WLS fibres. About 40% of the final calorimeter has been constructed, instrumented, tested and put into storage. In 2000 procurement of different electronics parts has started. About 25% of more than 10 000 PMT tubes have been delivered and tested. Production of electronics cards, HV power supplies and mechanical parts for drawer assembly has started. The calibration of stored modules will start in summer 2001.

Experimental Physics Division 25 Muon Spectrometer

The toroidal magnet system that provides the magnetic field for the muon detectors consists of a big barrel and two end-cap toroids. The engineering of the superconducting magnets has been completed for the major part and production in industry shows good progress. About 60% of superconductor and about 20% of the coil winding has been completed. The construction of the 10 huge vacuum vessels commenced. Contracts for cold mass and cryostat integrations were agreed. The construction of the 9 m long B0 model was completed and the coil was delivered to CERN in October 2000 for cryogenic testing. The Magnet Test Facility for on-surface proof testing of all toroids is complete and the test of a first model coil B00 has started. Specifications for cryogenic and vacuum services are complete and tendering of these systems has started. The toroids will be instrumented with Monitored Drift Tubes (MDTs) except in the very forward inner region, where Cathode Strip Chambers (CSCs) will be used. The muon trigger and second coordinate measurement for muon tracks are provided by Resistive Plate Chambers (RPCs) in the barrel and Thin Gap Chambers (TGCs) in the end- caps; both kinds of detector have good time resolution.

During 2000, the emphasis was placed on starting production of all the muon detectors. For the trigger chambers, production of the TGCs continued in Israel, where 700 chambers have been constructed, and started at KEK, where the module-0 chamber has been tested and 40 production chambers have been completed; also a new production site is being prepared in China. The front-end electronics have been produced and successfully tested. The first RPC production module has been tested, and series construction started, with three chambers completed and 24 at various stages of construction. For the tracking chambers, in the case of the MDTs, 10 production sites have produced their module-0 chamber; for eight of these sites their module-0 chambers have been measured in the X-ray Tomograph and found to be well within the specifications. The full production of chambers has started in three sites, where 38 chambers have been produced, reaching the expected production rate. The CSCs have successfully passed their PRR, and the construction of their module-0 is well under way.

Trigger and Data Acquisition

The trigger has three hierarchical levels. The level-1 trigger uses information from the calorimeter and from the muon-trigger chambers to search for high-transverse momentum muons, electrons, photons, isolated hadrons (taus) and jets, and large missing and total transverse energy. The level-2 trigger processes information from regions of interest identified by the first level, accessing the data from different detectors sequentially, making early rejection where possible. The Event Filter (level-3) processes information from the whole event. Detailed specification and design of the level-1 trigger are now well advanced, and full- functionality prototypes are being produced. New FPGA and ASIC technologies have been adopted to improve the flexibility of the level-1 design. The Technical Proposal for the higher-level triggers (level-2 and Event Filter), data acquisition (DAQ), and detector control system (DCS) was submitted to and accepted by the LHC Committee. The technical proposal reported on the successful completion of two multi-year developments, the Level-2 Pilot Project and DAQ/EF Prototype-1 project. The Pilot Project validated the level-2 trigger architecture concept by a combination of prototyping and simulation. The DAQ/EF–1 encompassed the movement of data from the detector to mass storage, event filtering, and overall control, configuring and monitoring of the online system. During 2000, it was applied successfully as the data- acquisition system for the tile calorimeter beam tests. Prototype Event Filter farms based on different processor technologies were studied. The Technical Proposal also presented an architecture for the HLT/DAQ/

26 Experimental Physics Division DCS system. This architecture is now being developed further as a joint trigger and data-acquisition project. DCS provides a distributed control system for the operation of ATLAS. In concert with the LHC Joint Controls Project (JCOP), a commercial Supervisory Control And Data Acquisition (SCADA) system was selected. Other key hardware and software building blocks for DCS were also developed, including a compact, radiation-tolerant microprocessor-based Embedded Local Monitor Board that will be used widely for control throughout ATLAS. Integration of the trigger, DAQ and DCS prototype systems started late in the year.

Computing

During 2000 work has continued on the migration from the Fortran-based software, used for the Detector and Physics Performance TDR (submitted in 1999), to a suite based on OO/C++. We are now in a position to start testing reconstruction using a C++ framework (Athena) and reconstruction codes written in C++ or ‘wrapped’ versions of the Fortran code. A major effort has been the testing and validating of GEANT4 for the ATLAS detector, by testing the GEANT4 physics processes and developing the necessary infrastructure, particularly for detector description. ATLAS is collaborating closely with the GEANT4 team, for example through monthly ATLAS/GEANT4 meetings. Another significant area of work has been to revise the planning schedule and estimates of effort required for the overall ATLAS computing project. We have also been developing our ideas and plans for ATLAS worldwide computing, with particular reference to our forthcoming series of Data Challenges. Members of ATLAS are participating in all the various GRID projects, and we expect the GRID to be a major component of our worldwide computing strategy. A policy of ‘software agreements’, as precursors to an eventual Computing Memorandum of Understanding, has been agreed, and is now being implemented. ATLAS has also participated vigorously in the CERN review of LHC computing.

Organizational Issues and Schedule

The ATLAS Collaboration consists of 150 participating institutions (October 2000) with 1850 physicists and engineers (700 from Non-Member States). Technical Design Reports (TDR) are produced for each detector system, and are refereed by the LHCC as a process for giving construction approval. The Memorandum of Understanding signed by all participating funding agencies specifies the deliverables expected from each participating institute. Most detector systems entered the construction phase during 2000. The whole construction project is described in a baseline schedule which is linked to the installation schedule. The baseline schedule contains milestones that are regularly monitored by the experiment management. The installation of ATLAS is expected to start at the beginning of 2003, and data-taking to begin with a four-week pilot run in April 2006, followed by a seven-month physics run starting in August 2006.

Compact Muon Solenoid (CMS)

The CMS Collaboration consists of 1809 members from 144 institutes and 31 countries (February 2001). Construction has started for all detector subsystems. Engineering Design Reviews (EDRs) of parts of these sub-systems have been successfully carried out. These are held prior to granting authorization for purchase. The tracking community rearranged the responsibilities for the all-silicon tracker and passed an EDR at the end of 2000. The Trigger Technical Design Report was submitted to the LHCC in December 2000. The

Experimental Physics Division 27 schedule for the LHC machine and the experiments has been revised and CMS will be ready for first collisions, now expected in April 2006. A brief description, together with the status, of each element of CMS is given below.

Civil Engineering

Civil-engineering works at Point 5 (located at Cessy, France) are advancing and the surface building (SX5) has been equipped on schedule. The 12 m and 20.4 m diameter shafts have been dug. The digging of the pillar between the underground caverns USC5 and UXC5 started after the end of LEP running. The excavation has now reached the level of the beam. There are significant delays in the civil-engineering work and the delivery of the underground cavern is now foreseen for April 2004.

Magnet

The detector (Fig. CMS–1) will be built around a long (13 m), large bore (diameter of 5.9 m) and high- field (4 T) superconducting solenoid. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12 500 tons. All the iron pieces for the barrel yoke have been delivered by the manufacturer (DWE, Germany). Three of the five barrel-yoke rings have been assembled at Point 5, including the central one comprising part of the outer vacuum tank for the coil (Fig. CMS–2). The three discs of the first end-cap have been trial-assembled at the manufacturer (Kawasaki, Japan), then dismantled and dispatched. The assembly of the end-cap yoke will start at Point 5 in April 2001. The barrel feet and the end-cap carts have been delivered to CERN from SES, Pakistan and Hudong Shipyards, China, respectively. Three lengths of superconducting strands, each of length 320 km, have been delivered by Outokumpu, Finland. This corresponds to about 50% of the required length. Four good lengths of Rutherford cable, out of 21, have been produced at Brugg Kabelwerk, Switzerland. Each one has a length of 2.65 km. Three lengths of the insert (Rutherford cable co-extruded with pure aluminium) will soon be produced at Cortaillod, Switzerland. The electron-beam-welding line is being tested at Techmeta, France. The design of the winding machine has been completed at Ansaldo, Italy and contracts have been placed. The magnet test is scheduled to finish in the surface building by July 2004. The magnet project is on schedule and within the foreseen budget.

C.M.S. Compact Muon Solenoid 1.23 % 6.61 m 0.00 m 3.954 m 1.268 m

10.83 m .8cm .5cm η = 1.1 η = 1 η = 0.5 g 7.430 m 7.380 m MB/2/4 MB/1/4 MB/0/4 Y 6.955 m 7.000 m YB/2/3 YB/1/3 YB/0/3 MB/2/3 MB/1/3 MB/0/3 ME/1/3 5.975 m Z η = 1.479 YB/2/2 YB/1/2 YB/0/2 MB/2/2 MB/1/2 MB/0/2 ME/4/2 ME/3/2 ME/2/2 YB/2/1 YB/1/1 YB/0/1 4.905 m MB/2/1 MB/1/1 MB/0/1 4.020 m 3.800 m

ME/1/2 CB/0 YE/3 η 2.950 m = 2.4 YE/2 2.864 m 2.700 m HB/1 YE/1 HE/1 1.932 m ME/4/1 ME/3/1 η = 3.0 ME/2/1 1.700 m 1.790 m 1.750 m ME/1/1 EB/1 1.290 m 1.185 m HF/1 EE/1 SB/1 η = 5.31 0.440 m 0.00 m SE/1 9.75 m 8.49 m 7.24 m 6.68 m 5.68 m 6.45 m 4.25 m 3.88 m 10.86 m 14.96 m 14.56 m 10.63 m 2.935 m 0.000 m 14.53 m 10.91 m .25cm Fig. CMS–1: The transverse view of CMS.

28 Experimental Physics Division Fig. CMS–2: Two barrel yoke rings assembled in the surface building (SX5) at Point 5.

Inner Tracking

The inner-tracking subsystem has been designed with the principal objectives of efficient reconstruction and precision momentum measurement of high-transverse-momentum charged tracks. The tracking volume is given by a cylinder of length 6 m and diameter 2.6 m. Solid-state microstrip detectors provide the required granularity and precision in the bulk of the tracking volume. Pixel detectors placed close to the interaction region improve the measurement of the track impact parameter and reconstruction of secondary vertices.

In June 2000 the LHCC approved the ‘All-Silicon Tracker’, to be built in a single stage. The responsibilities have been shared and the costs have been updated. The layout has been optimized with the removal of the central support tube. A preproduction comprising 200 detectors has been launched to exercise the automated production procedure. An EDR was passed to enable the launch of the tender for silicon sensors.

The short bunch-crossing time at the LHC (25 ns) places challenging requirements on the readout electronics. Furthermore, the detectors and the readout electronics have to withstand high levels of irradiation. A test in an LHC-like bunched beam was successfully carried out to test the functionality of the full electronics chain. Beam tests using electronics designed in 0.25 µm technology have confirmed the expected improved performance over electronics designed in DMILL. A system test with the final readout electronics will be carried out in the autumn of 2001.

Good progress is also being made on the electronics and mechanics of the pixel detectors.

Experimental Physics Division 29 The Muon System

Centrally produced muons are measured three times: in the inner tracker, after the coil and in the return flux. They are identified and measured in four identical muon stations inserted in the return yoke. Each muon station consists of many planes of aluminium drift tubes (DTs) in the barrel region and CSCs in the end-cap region. The four stations include RPCs triggering planes that also identify the bunch crossing and enable a cut on the muon transverse momentum at the first trigger level.

Facilities for mass production have been set up in the institutes that will participate in the construction of the muon chambers. A preproduction DT chamber has been assembled using the final assembly tools and procedures. The commissioning of two additional barrel DT assembly lines is nearly complete. The production of cathode I-beams and plates with field-shaping electrodes has started in Bologna and Turin. respectively. Around twenty CSCs have been manufactured at Fermilab. Parts and tooling have been procured for the sites at PNPI, St. Petersburg and IHEP, Beijing. The procurement of parts for the barrel RPCs also commenced in 2000. The community working on the forward RPCs has been strengthened and the designs have been finalized. Much work has been carried out on the integration and installation of the muon chambers. Mass production of DTs and CSCs at various sites is expected to reach the final rates at the end of 2001.

The Electromagnetic Calorimeter (ECAL)

Scintillating crystal calorimeters offer the best performance as far as electromagnetic energy resolution is concerned. Lead tungstate (PbWO4) has been chosen because it offers the best prospects of meeting the diverse requirements for operation at the LHC. The scintillation light is detected by silicon avalanche photodiodes (APDs) in the barrel region and vacuum phototriodes (VPTs) in the end-cap region.

The preproduction (6000) of crystals from Russia has been completed. The yield of good crystals, satisfying the optical and mechanical specifications, has now reached the desired value. A contract for a further 30 000 crystals has been placed in Russia. The crystal producers in China, using 28-fold pulling furnaces, have delivered a few hundred crystals that are being evaluated. The production of all the required crystals (~80 000) is expected to take four years. The infrastructure at the centres where the crystals will be assembled into modules for installation has been set up. The photodetectors, meeting the specifications, have been developed in collaboration with industry. A small fraction of APDs were dying after accelerated aging and irradiation. The problem has now been overcome and production will start soon. The preproduction (500) VPTs, meeting the specifications, have been delivered by RIE, St Petersburg. The front-end chain consists of preamplifier/range selector (FPPA), ADC and a serializer/optical link. The final FPPA has been submitted to Intersil, USA. The order for the ADC (Analog Devices, USA) will be placed soon. A 0.25 µm version of the serializer has been chosen.

Photon–π0 separation in the forward region requires a preshower detector in front of the crystals. Acceptable silicon sensors have now been produced in Russia, Taiwan and India. A large dynamic range preamplifier in a radiation-hard technology has been fabricated and successfully tested.

30 Experimental Physics Division The Hadronic Calorimeter (HCAL)

The HCAL has three geometrically distinct parts. The central pseudorapidity range |η| < 3.0 is covered by the barrel and end-cap parts, while the region 3.0 < |η| < 5.0 is covered by the forward calorimeter.

The barrel and end-cap brass/plastic scintillator sampling calorimeters sit inside the 4 T field of the CMS solenoid. The absorber for the first half-barrel (18 wedges) was trial-assembled at Felguera, Spain (Fig. CMS– 3). It was dismantled and the wedges have been delivered to CERN. The optics, scintillator plus the fibres, for more than half the barrel wedges have also been manufactured and delivered to CERN. The trial assembly of one end-cap is nearing completion at the manufacturer, MZOR, Belarus. The light is detected by photodetectors (proximity-focused hybrid photodiodes) that can provide gain and operate in high axial magnetic fields. These have been developed in collaboration with industry.

Fig. CMS–3: Trial assembly of the first HCAL half-barrel at Felguera, Asturias in Spain.

The forward hadron calorimeter consists of steel absorber with quartz fibres, laid parallel to the beam line, as active medium. As they cross the quartz fibres the charged particles produce Cherenkov light that is channelled to photomultipliers. The geometry was changed from bricks to 18 wedges per side. The fibre spacing was changed from 2.5 mm to 5 mm but the packing fraction was preserved. A full-size prototype with a few diffusion-welded blocks of the new design will be made in mid-2001.

Trigger and Data Acquisition

The trigger and data acquisition consists of four parts: the detector electronics, the calorimeter and muon first-level trigger processors, the readout network and an online event filter system.

The CMS Level-1 trigger decision is based upon the presence of physics objects such as muons, photons, electrons, and jets, as well as global sums of Et and missing Et (to find neutrinos). Prototypes of demonstrator systems have provided proof of principle of the critical components of the Level-1 trigger-primitive generation, regional processing and decision logic. A detailed description in object-oriented (OO) computer code (CMS reconstruction program ORCA, written in C++) of signal generation and digitization in the

Experimental Physics Division 31 electronics chains have been used to estimate the trigger rates. In and out of time pile up has been simulated. The details are documented in the Level-1 Trigger TDR that was submitted at the end of 2000.

The Level-1 Trigger System is initially expected to reduce the bunch-crossing rate of 40 MHz to an event rate of 75 kHz. Each physics event (1 Mbyte large) is contained in about 500 front-end buffers (readout units). The data acquisition (DAQ) system has to assemble the event into a single processor in a ‘farm’ for executing physics algorithms so that the design input rate of 100 kHz is reduced to the 100 Hz of sustainable physics. It is impractical to envisage a full prototype of the CMS DAQ. Its development therefore has two components: the prototyping of a few key elements (e.g. the readout (RU) and filter (FU) units), and the use of simulation to study the behaviour of these units in a large 500 by 500 configuration.

The development and evaluation of RU and FU prototypes, together with various switching technologies, has continued. A new event builder set-up has been installed that consists of 64 Intel PCs interconnected by two networks based on the most advanced technologies currently available: a 64-port Gigabit Ethernet (Foundry, USA) and a 128-port Myrinet switch (Myricom, USA). The PCs are used to emulate the main elements of the CMS event builder, namely the readout units, the builder units, the filter units and the event manager. The set-up will be used to evaluate all the software and hardware design options that will be considered for the TDR, foreseen for the end of 2002.

Software and Computing

For complex systems, such as the CMS detector, an OO approach, implemented in C++, is now the choice of software developers. CMS is moving to such a software design. The move to this mainstream software technology will help to manage the process of change over the long lifetime of the experiment.

The CMS reconstruction program, ORCA, has evolved into an operational system for detector, trigger and physics studies. The OO technology has been used in the production of Level-1 and High-Level Trigger (HLT) simulation data.

The data storage, networking and processing power needed to analyse CMS data is well in excess of that of today’s facilities. The present production represents roughly 1% of the system needed in 2006. The planning includes a 5% mock data challenge for 2002, and a 20% stress test of the whole chain in 2004/5.

Technological advances will help to make the data analysis possible in a distributed environment, where physicists are scattered all over the world. The optimum mix of storage, networking and processing will change as technology develops. CERN has carried out a Computing Review (the Hoffmann Review) in which all LHC experiments participated. The review evaluated the current situation, plans and prospects of data management and computing at the LHC. A multi-tier model, similar to that developed by the MONARC project, underpinned by GRID technology to provide efficient resource utilization and rapid turnaround time will be prototyped.

32 Experimental Physics Division Physics Reconstruction and Selection

With the construction phase starting in earnest, physics simulation work has begun to focus on the development of the eventual reconstruction code. As mentioned above this development is taking place using C++ and OO methods. CMS has decided that the first priority is a full understanding and verification of the HLTs. Since CMS does not employ distinct physical intelligences for the would-be Level-2 and Level-3 triggers, but only a single processor farm, the task of selecting events is intimately linked with that of reconstructing the associated detector information online. With this in mind, four ‘Physics Reconstruction and τ Selection’ (PRS) groups were started (electron/photon, muon, jet/missing Et, and b/ vertexing) in April 1999. The aim of the groups is to develop the reconstruction and selection procedures (algorithms and software) starting from the output of the Level-1 trigger, and aiming ultimately at the full off-line reconstruction. During 2000, the four groups delivered the first algorithms that correspond to a reduction of the event rate after Level- 1 by about a factor of 10 using information from single CMS subdetectors. With the original term of the PRS groups ending in December 2000, the activity now continues as a new CMS project, the PRS project, which has close ties with the Computing and Trigger/DAQ projects. The PRS groups are now working on reconstructing physics objects using information from multiple CMS subdetectors.

Physics

The physics performance of the individual subdetectors is summarized below.

TRACKER: in high-pt events the track finding efficiency for tracks not interacting in the tracker is > 96% |η| ∆ ≈ for pt > 2 GeV and within < 2.5. The momentum resolution is pt/pt 0.15 pt +0.5% (pt in TeV). The use of pixel detectors close to the interaction point leads to a b-tagging efficiency of ~ 50% for a rejection of ~ 100 against non-b jets.

ECAL: the mass resolution for a 100 GeV Higgs boson decaying into two photons is found to be 650 MeV at low luminosity and 690 MeV at high luminosity. A large fraction of the conversions are recovered when an appropriate energy-clustering algorithm is used.

HCAL: the missing-energy resolution is not much degraded w.r.t. an ideal detector response. The jet–jet mass resolution for Ws from heavy Higgs bosons is found to be about 8.5 GeV. In the search for a low-mass Higgs boson an interesting channel is qq → qqH (H →ττ). Maximization of the S/N requires dedicated τ- triggers, efficient forward-jet tagging and good missing-transverse-energy resolution to enable cuts to be placed as low as 30 GeV.

MUONS: the excellent momentum resolution of the muon and inner tracking system is reflected in a mass resolution of about 1 GeV for a 150 GeV Higgs boson decaying into ZZ*, each of which in turn decays into two muons.

There are strong physics arguments for supersymmetry (SUSY). Squarks and gluinos weighing up to 2 TeV can be detected, using as signature events with one or more charged leptons, missing transverse energy and two or more jets. Sleptons weighing as much as 400 GeV can be found by looking for events without hadronic jets, but with lepton pairs and missing transverse energy having distinctive kinematic characteristics. Three-lepton states are particularly promising for the detection of charginos and neutralinos. In many cascade

Experimental Physics Division 33 decays a heavier neutralino is produced that subsequently decays into the lightest one with the emission of a pair of charged leptons. For low to moderate values of tanβ the spectrum of the dilepton invariant masses shows a strikingly sharp end-point determined by the difference in neutralino masses. This feature can be used to select and almost fully reconstruct some events yielding e.g. the mass of the bottom squark.

The above studies of specific SUSY models indicate that it is possible to detect a large fraction of the expected SUSY spectrum in CMS. Within the SUGRA models it should be possible to determine the fundamental parameters at the GUT scale.

Work has been carried out to obtain a detailed understanding of the capabilities of CMS for heavy-ion physics, especially for signatures involving dimuon production, jet quenching and Z production. A detailed document outlining the capabilities of CMS has been prepared.

ALICE (A Large Ion Collider Experiment)

ALICE is a general-purpose heavy-ion detector designed to study the physics of strongly interacting matter and the quark–gluon plasma in nucleus–nucleus collisions at the LHC. It currently includes more than 900 physicists and senior engineers — both from nuclear and high-energy physics — from about 70 institutions in 25 countries.

The detector is designed to cope with the highest particle multiplicities anticipated for Pb–Pb reactions (dN/dy up to 8000) and it will be operational at the start-up of the LHC. In addition to heavy systems, the ALICE Collaboration will study collisions of lower-mass ions, which are a means of varying the energy density, and protons (both pp and p–nucleus), which provide reference data for the nucleus–nucleus collisions.

ALICE (see Fig. ALICE–1) consists of a central part, which measures event-by-event hadrons, electrons and photons, and a forward spectrometer to measure muons. The central part, which covers polar angles from 45° to 135° over the full azimuth, is embedded in the large L3 solenoidal magnet. It consists of an inner tracking system (ITS) of high-resolution silicon tracking detectors, a cylindrical TPC, three particle identification arrays of time-of-flight (TOF), ring imaging Cherenkov (HMPID) and transition radiation (TRD) detectors and a single-arm electromagnetic calorimeter (PHOS). The forward muon arm (2°–9°) consists of a complex arrangement of absorbers, a large dipole magnet, and fourteen stations of tracking and triggering chambers. Several smaller detectors (ZDC, PMD, FMD, CASTOR, T0) are located at forward angles.

The experiment was approved in February of 1997. The final designs of the different detector systems have been laid down in the Technical Design Reports between mid 1998 and early 2001. The Memorandum of Understanding was submitted in early 2000 and has been signed by most funding agencies. Construction has started for a number of detector systems.

34 Experimental Physics Division Fig. ALICE: 3-D view of the detector.

Inner Tracking System (ITS)

The main purpose of the ITS is the detection of secondary vertices (hyperons and charm) and the standalone track finding of low-momentum charged particles. The system consists of six cylindrical layers of coordinate-sensitive detectors, covering the angular range 90 ± 45°. The innermost planes consist of silicon pixel detectors and silicon drift detectors, whereas the two outer layers are made from silicon microstrip detectors.

Silicon Pixel Detectors: The engineering run of the ALICE front-end pixel chip in 0.25 µm technology was submitted to the foundry in July and chip tests have been ongoing since October. The chip is functional and satisfies the main SPD requirements. Measurements continue in order to optimize the working point and determine the spread of parameters. Bump-bonding trials have been started with two suppliers using different processes. The pilot chip design has been completed and submission scheduled in early 2001. Samples of the ladder bus have been produced and tested. A detailed study of the on-sector cooling has been completed and the model has been verified by measurements.

Silicon Drift Detectors: During 2000 the final ALICE design of the very large area SDD was tested on a high-energy pion beam and the tender for the detector production was launched after a PRR. The half-scale prototype of the radiation-tolerant first front-end chip was produced and successfully tested before and after irradiation. The data compression ASIC is under test and the full-scale prototype of the radiation-tolerant version of the last readout ASIC is under way. The preproduction of the ladder structure for the mechanical support has been tested, and the final production will begin in the first quarter of 2001. Prototype work on the cooling system continues after a temporary pause due to financial problems; a final decision is expected by August 2001.

Experimental Physics Division 35 Silicon Strip Detectors: The front-end electronics for the silicon strip layers has been redesigned in 0.25 µm technology in order to improve radiation and latch-up tolerance. The new chip (HAL25) has the same functionality as the previous one (A128C) but with an improved pad layout to facilitate assembly using microcables; the prototype will be submitted in early 2001. The orientation of the strips on the silicon detectors was optimized to improve the pattern recognition. Following the PRR, the detector market survey has started. The production of the carbon support structure is under way and approximately half the needed ladders have already been produced. The user requirements for the readout chain have been collected and the design has been initiated. The end-cap electronics will have to be adapted to the new front-end chip using deep submicron technology. Design and implementation has started for the databases needed to keep track of the production process.

Time Projection Chamber (TPC)

The TPC, the main tracking detector of ALICE, is central to the design of the experiment. Its task is track finding, momentum measurement and particle identification by dE/dx. The R&D phase has been completed for the readout chambers and is in its final phase in the areas of field cage and electronics. The field cage consists of a thin but stable cylinder serving as low mass and gas-tight support structures for the field strips which define the electrical drift-field. A 1 m3 prototype field cage and prototype readout chambers have been constructed and intensively tested. Following the PRR, procurement of the field cage has started and construction of the inner readout chambers will commence in April 2001. The electronics chain, whose design underwent a number of changes in 1999, will be based on a CERES-type preamplifier–shaper plus a commercial 10 bit, 10 MHz flash ADC, followed by a digital chip whose main functions are tail cancellation, baseline subtraction, zero suppression, and data formatting. Design of the electronics chain, including a new preamplifier–shaper chip and digital chip, is well under way and a decision on a commercial ADC will be taken early next year.

Particle Identification System (PID)

Particle identification over a large part of the phase space and for many different particles is an important design feature of ALICE. ALICE has three detector systems dedicated exclusively to PID: a TOF array optimized for large acceptance and average momenta, a small system (HMPID) specialized on high- momentum hadrons, and a TRD for electron identification above 1 GeV/c which was added to ALICE in the course of 1999. In addition, both tracking systems (ITS and TPC) provide energy-loss information which is important for electron identification and for hadrons of low momentum.

Multigap Resistive Plate Chambers (MRPC) for TOF

The TOF detector, with a total area of about 140 m2 and 160 000 channels, will identify pions, kaons and protons produced in the central region with momentum below about 2.5 GeV/c. The TOF TDR was submitted and approved in 2000; an addendum will be submitted in 2001. Several different prototypes were tested in 2000. The first full-size strips with 96 pads were built and tested, confirming the expected performances in terms of intrinsic time resolution (better than 80 ps) and efficiency (more than 95%). A first prototype of the central module of the TOF detector has been built and tests began at the end of 2000 with new front-end electronic cards equipped with commercial amplifiers and a first version of high-resolution TDC chips.

36 Experimental Physics Division High Momentum Particle Identification Detector (HMPID)

The HMPID is a proximity-focusing Ring Imaging CHerenkov (RICH) using a liquid radiator, in conjunction with a reflective CsI photocathode, evaporated on the pad segmented cathode of a multiwire proportional chamber. The optimization of the detector parameters has been completed with the help of Monte Carlo simulations. The design was changed with respect to the TDR for a number of items: radiator thickness (15 mm), pad-plane production technology (multilayer PCBs) and Front-End Electronics (FEE) implementation (SMD connectors), and module layout (FEE cooling and reinforced cathode frame mechanical structure). The engineering design of the main components of the HMPID modules has been finalized and, following the PRR, procurement of a number of items has started. A new small prototype (PROTO-3) has been built to perform further beam tests of finalized detector components. The final version (0.7 µm technology) of the FEE chip, GASSIPLEX, has been produced and validated. The design of the second version of the DILOGIC chip, which performs the data reduction, has been completed.

The large-area ALICE prototype, representing two-thirds of the final ALICE module, was installed in 1999 into the STAR detector at RHIC and has been smoothly operated during the data-taking period with Au- colliding beams. Data analysis is in progress, preliminary results have already been shown at conferences.

Transition Radiation Detector (TRD)

The transition radiation detector (TRD) for ALICE will identify electrons with momenta above 1 GeV/c to study production rates of quarkonia and heavy quarks (charm, beauty) near midrapidity. It consists of six layers of xenon/CO2-filled wire chambers preceded by a composite radiator (foam and fibres) and will cover the central (barrel) region of ALICE between TPC and TOF. However, with the currently available funding about half of the detector will have to be staged.

Measurements using secondary beams at GSI have shown that the detector will be able to meet the requirement for a pion detection efficiency of less than 1% at 90% electron efficiency above 1 GeV/c. A recirculating gas system has been tested and construction of a full-scale prototype of minimal radiation thickness is under way. Two FEE prototypes (preamplifier/shaper and digital processor) have been designed and tested. In cooperation with the ALICE TPC a very low power, 10 bit, 10 MHz ADC has been identified for digitization of the pulses. A first design of the detector is fully implemented in ALIROOT and a tracking package has been developed. Simulation studies have shown that as a function of multiplicity the space point resolution, momentum resolution, efficiency, and tracking trigger performance are satisfactory even at dN/dy = 8300. The evaluation of electron/pion separation at large dN/dy is currently under study. The TRD group is planning to submit its Technical Design Report in mid-2001.

Photon Spectrometer (PHOS)

The PHOS detector is a single-arm, high-resolution electromagnetic calorimeter made with lead-tungstate π0 η (PbWO4) crystals designed to search for direct photons and to measure and spectra at high momentum.

A new industrial facility has been found in Russia (Apatity) for the mass production of the PbWO4 crystals. The Czochralski growth technology was installed at the Apatity plant and some 300 ingots of length

Experimental Physics Division 37 27 cm have been grown. A sample batch of 10 crystals of a rectangular shape of 2.2 × 2.2 × 18 cm3 has been produced and tested with the optical and radioactive-source test benches in the laboratory, and with high- energy electrons in beam. The tests demonstrated that the crystals are of the same quality as those previously produced elsewhere. An R&D for the industrial crystal cutting technology is under way. A 256-channel prototype electromagnetic calorimeter equipped with a new cooling/thermostabilization system, an LED monitoring system, a readout electronics and a charged-particle veto detector has been manufactured and tested in the laboratory.

Forward Muon Spectrometer

The forward muon arm is designed in order to cover the complete spectrum of heavy-quark resonances, i.e J/Ψ, Ψ′, Υ, Υ′, Υ′′. It will measure the decay of these resonances into muons, both in proton–proton and in heavy-ion collisions, with a mass resolution sufficient to separate all states.

Dipole Magnet: The main activities in 2000 were devoted to the finalization of the magnet design. A full manufacturing design report was written at the end of June. This was followed by a PRR for the magnet, which led to a call for tender for the supply of the aluminium conductor and the production of the excitation coils. The manufacturing of the yoke and related equipment, i.e. all support structures, will be done by JINR. The R&D work included the completion and test of a full-scale prototype of a single-layer winding and the fabrication of a 1:10 scale mock-up. As a consequence of project reorganization the design activity needs to be extended and will continue until production of the major components begins in 2001.

Muon Tracking Chambers: More precise simulations taking into account mechanical details of the set-up (flanges, bellows, etc.) have shown a significant increase of the charged-particle background in the tracking chambers, in particular for Stations 1 and 2. In order to reduce the occupation factor and to increase the geometrical efficiencies, a new frameless chamber design has been adopted, together with a new internal chamber geometry (decrease of the pad size, of the anode–cathode gap and of the anode pitch by 20%). Beam tests of the new design have given good results. For the FEE, the first prototype has been completed for MANAS (preamplifier–filter–shaper) and for MARC (numerical ASIC). The results are quite satisfactory and the final version is being designed. New MCMs with smaller area have been designed to accommodate the decreased pad size and will be tested on a full-size slat in mid-2001. Several cooling schemes for Stations 1 and 2 have been experimentally tested in a full-size set-up of one-quarter of the final system.

Muon Trigger Detectors: The dimuon trigger is based on single-gap RPCs. Extensive tests of different prototypes carried out at the SPS, PS and GIF (Gamma Irradiation Facility) indicate that the required performances (rate capability, space and time resolution) can be achieved by RPCs of low resistivity operated in streamer mode. Full-scale prototype and long-term aging tests are in progress at GIF to finalize the choice of materials. At present, the best candidate is a bakelite plate with a thin layer of melamine coated with linseed oil on the gas side, with a bulk resistivity of a few 109 Ωcm. A significant improvement of the time resolution (σ < 1 ns) has been achieved by a new-concept FE chip, especially designed for the streamer mode, based on a dual-threshold discrimination technique. The final chip (8 ch.) is expected for the end of this year. The test bench for the mass production is now almost ready. The second generation of the local trigger electronics is designed (VME 9U board) and has been sent for manufacturing. The test bench, including dedicated 128 bit pattern generators at 40 MHz speed, will be completed in the next few months.

38 Experimental Physics Division Forward Detectors

ALICE uses a number of smaller detector systems (ZDC, PMD, FMD, CASTOR, T0) located at small angles to define and trigger on global event characteristics; in particular, impact parameter and event reaction plane.

Four small and very dense calorimeters (Zero Degree Calorimeters, ZDC) are located about 100 m inside the machine tunnels on both sides of the interaction. A call for tender has been made for the procurement of the dense material used as absorber in the neutron calorimeters. A prototype of an electromagnetic calorimeter has been tested; this calorimeter will be used to improve the centrality trigger when nuclear fragments are produced in peripheral collisions and remain undetected in the beam pipes. A similar calorimeter (CASTOR), located closer to the interaction region opposite the muon arm, will measure electromagnetic and hadronic transverse energy at large rapidity. A prototype comprising three reading units (~ 25% of one octant) was tested in September 2000.

The Photon Multiplicity Detector (PMD) will search for non-statistical fluctuations in the ratio of photons to charged particles, measure collective flow and transverse energy of neutral particles, and in addition determine the reaction plane. It consists of a few m2 preshower detector (a lead converter sandwiched between two planes of cellular honeycomb gas detectors) and is mounted behind the TPC opposite the muon spectrometer. The final location is currently being re-examined in order to minimize the material in front of the detector. Several prototypes were tested with both electron and pion beams.

The FMD detector (baseline: silicon pad detectors) will measure charged-particle multiplicity over a large fraction of phase space (|η| < 4); the T0 counters (baseline: 24 Cherenkov radiators with PMT R/O) will provide the event time with a precision of less than 50 ps. Both detectors are currently at the conceptual design stage.

Trigger and DAQ

The ALICE trigger prototype developed for the NA57 experiment was integrated with DATE (see below) and used for data-taking in October 2000. The system worked successfully, and 220 million triggers were taken. A draft User Requirement Document for the Central Trigger Processor (CTP) has been prepared after discussion at three workshops held in 2000.

New physics observables which require the full utilization of the available luminosity demand a high-level trigger system (Level-3 Trigger). Various Level-3 data compression algorithms (lossy/lossless) were implemented and tested using simulated ALICE events; with standard techniques they reached a reduction factor of about two compared with the 8-bit encoded TPC zero-suppressed raw data. A fast Level-3 cluster finder and track follower, originally developed for the STAR Level-3, has been adapted to the ALICE TPC detector, but alternative fast pattern-recognition techniques are studied as well. The STAR Level-3 developed by members of the ALICE Level-3 group ran as online trigger processor at STAR turn-on and is a success.

A data-flow pattern was developed and MPI was studied extensively as potential network abstraction layer. The interfaces of the Level-3 system are being defined. An implementation exists, including various data communication objects which were tested and compiled to a first system implementing the full chain

Experimental Physics Division 39 from the PCI data sources up to the track merger. The chain was tested with simulated data. A test cluster with 50 nodes has been acquired for use in ongoing system integration tests.

The relatively short heavy-ion running periods determine the main features of the DAQ. In order to collect a sufficient number of events for physics analysis, the DAQ system has to be designed with a very large bandwidth: up to 1.25 Gbyte/s on mass storage. A general framework called the ALICE Data Acquisition Test Environment (DATE) system has been developed as a basis for prototyping the components of the DAQ and to support the present activities of the ALICE Collaboration in test beams. It is also in use in several other experiments: NA57, NA60, COMPASS and HARP. A prototype of the Detector Data Link (the optical link interfacing the DAQ and the detector electronics) has been developed and interfaced with the DATE system. The integration of this link is starting with the TPC and SDD readout electronics. Work has been pursued in the area of mass-storage systems that is crucial for ALICE. During the third ALICE Data Challenge (early 2001), the event building has been demonstrated to scale up to 350 Mbyte/s. A total of more than 50 Tbyte of data has been collected and archived with DATE at an average rate of 60 Mbyte/s, formatted with the ROOT I/ O package and stored in the CASTOR mass-storage systems.

Offline

A new offline framework has been developed since 1998 in coincidence with the writing of the detector Technical Design Reports. The offline project has developed a system for the simulation and reconstruction, and at the same time it has performed the transition to the object-oriented (OO) programming techniques via the involvement and training of the community of the users.

All code is based on the OO paradigm, and is developed using the C++ programming language. The ROOT framework is the base for this development, integrating the GEANT3 and GEANT4 simulation packages into it. A parallel effort started to integrate also the FLUKA package. At present all the ALICE offline production code is in C++. A first version of the complete framework, from simulation to reconstruction and analysis, will be completed shortly in order to run a first large virtual ALICE experiment in the framework of the Physics Performance Report.

The ALICE offline project has taken an active role in the EU DataGRID Project by deploying and testing distributed computing solutions for the remote submission and retrieval of jobs.

LHCb

Magnet

A dipole magnet with an iron yoke of about 1500 t and an aluminium normal conductive coil providing an integral field of 4 Tm will be used for the LHCb experiment.

After the approval of the Technical Design Report (TDR) by the Research Board in April, further optimization work continued until June. Particular care was taken to reduce the fringe field of the magnet. In June, the call for tender was sent out for three items, the iron yoke, the aluminium conductor and the coil

40 Experimental Physics Division construction, to those firms who had replied to the market survey. The tendering procedure has finished and the orders are being sent out.

Vertex Locator (VELO)

The design parameters of the detector were reoptimized for physics. Because of the new design of the wake-field suppressor, the silicon sensor can be brought closer to the beam than anticipated in the Technical Proposal, thus reducing the contribution of multiple scattering to the vertex resolution. The outer radius of the detectors was reduced and the number of stations was increased in order to preserve the acceptance. As a result, the average number of hits per track has increased giving more redundant track reconstruction. The number of readout strips was reduced by 10% without deteriorating the resolution. The resolution and efficiency of the detectors after heavy irradiation corresponding to several years of LHCb running were studied using the SPS beam.

A first version of a complete front-end chip in 0.25-micron technology was submitted for production in June. Chips were received in October and are being tested. Another design of such a chip based on the radiation-hard DMILL technology was submitted in November. A predecessor of this chip (SCTA) is now regularly used in our test beam. Design of the off-detector electronics board is in progress, and a prototype board including the FADCs is being tested.

The design of the vacuum tank and the mechanics is now almost complete. It was presented to LEMIC, and then discussed in subsequent meetings with the LHC vacuum and RF groups. Various studies are under way to fulfil the machine requirements. The Technical Design Report of the VELO is scheduled for May 2001.

Inner Tracker

The inner tracker of the LHCb experiment covers the region close to the beam pipe where the particle density is very high. Our exhaustive test-beam studies show that a micropattern gaseous detector with triple GEM foil can operate in a stable condition with the expected particle density. The triple-GEM detector has an advantage over silicon microstrip devices in that larger sensor planes can be built without increasing the number of readout channels. However, the occupancy of the triple-GEM chambers in the innermost region becomes too high to guarantee efficient tracking. Therefore, LHCb is studying the option of operating a silicon microstrip detector in parallel.

Engineering studies of the tracking stations with silicon microstrip detectors are in progress. Evaluation of the optimal parameters of the silicon sensors was performed and detailed specification fixed. A few examples of two different prototype sensors have been ordered from two different companies. They will be tested at the Paul Scherrer Institute at a high rate, and at CERN to measure position resolution with high-momentum particles.

The final decision on the layout and technology depends on the simulation studies of the particle density, taking into account the beam pipe, cables for the detectors and other details. The Technical Design Report of the inner tracker is scheduled for December 2001.

Experimental Physics Division 41 Outer Tracker

The outer tracker of the LHCb experiment is based on straw technology. The straw tubes have a cell size of 5 mm and lengths up to 3.6 m, with wire supports inside the tubes at every 50 cm. The longest prototype modules so far tested in the beam were 2 m long and gave encouraging results.

Test-beam results show that a gas mixture of Ar(70%)/CF4(25%)/CO2(5%) fulfils the LHCb requirements: the maximum drift time is well below 50 ns even for those chambers placed in the dipole magnet. Almost 100% efficiency per drift cell is achieved and a spatial resolution of 0.2 mm per cell is obtained. Cross-talk between neighbouring cells is 0.5% in amplitude.

The aging effect of the chambers has been studied. In addition to local irradiation with pencil beams, X- rays and radioactive sources, 2 m prototypes have been installed in the HERA-B detector providing a realistic global irradiation. During the run, no apparent signs of aging were observed. The behaviour of the irradiated prototypes is being compared in detail with that of non-irradiated ones in a PS test beam. So far, no degradation of the performance has been seen.

Designs of the tracker stations are in progress. Particular care is being taken to reduce the amount of material as much as possible. It might be possible to reduce the material of the station to as little as 2% of a radiation length.

The baseline solution for the readout electronics is being designed using a TDC chip developed for other LHC experiments. Preproduction chips will be available in autumn 2001 and a small number of test samples are already in hand. Although acceptable, this TDC is not ideally suited to our purposes. Therefore, development of a dedicated TDC chip has started and complete prototypes are expected in early 2002. The Technical Design Report of the outer tracker is scheduled for September 2001.

RICH

The Technical Design Report for the RICH system was submitted in September to LHCC. It was recommended for an approval in November. In addition to the development of a detailed engineering design for the two detectors, RICH-1 and RICH-2, successful tests of the mirrors and their support structures have been carried out.

For the photon detector, the Pixel Hybrid PhotoDetector (HPD) was selected as baseline at the beginning of this year, with the MAPMT being retained as a back-up solution. During this year, good progress has been made towards the final Pixel HPD. The design of the pixel chip, developed in conjunction with the ALICE experiment, has been submitted to the manufacturer, although delayed by a few months with respect to the original schedule. The chips were delivered in December and are being tested.

The rest of the tube, consisting of an 80 mm diameter quartz window with photocathode, and electrostatic focusing to demagnify the image onto the silicon sensor, has been successfully tested with prototype tubes. All the components necessary to encapsulate the pixel sensor and the readout electronics into a tube are ready.

42 Experimental Physics Division Calorimeter

The Technical Design Report for the calorimeter system was submitted in September to LHCC. It was recommended for an approval in November. The system is optimized for the first stage of the trigger by detecting a single high-pt hadron, electron or photon. It consists of a scintillator pad detector combined with a preshower counter, followed by a ‘shashlik’-type electromagnetic calorimeter and a hadron calorimeter based on the iron/scintillator tile technology developed for the ATLAS experiment. A similar shashlik-type electromagnetic calorimeter has been successfully commissioned at HERA-B.

All the detector parameters were fixed and basic mechanical designs completed. For the choice of the parameters, the following points were considered:

– Level-0 trigger efficiency;

– hadron, electron and photon identification;

– high and medium energy π0 reconstruction;

– optimization of cost and construction effort.

A complete calorimeter system was prototyped and tested in the test beam, giving the expected performance.

Production of module-0 prototypes with exactly the same parameters as the final detectors is being prepared in order to establish the necessary tools and to optimize the production process and some design details.

A common front-end electronics will be used for the electromagnetic and hadron calorimeters. A preamplifier chip capable of working with 40 MHz bunch-crossing rate without introducing any spillover effect from the previous bunch crossing has been developed. It has been successfully tested in the test beam using the prototype calorimeters. A prototype of the front-end card operating in 40 MHz has been built. It contains the preamplifier, the ADC, signal treatment, and Level-0 pipeline buffers. The card was successfully tested in the test beam. Modifications of the card have been studied to cope with Single Event Upset problems, while keeping the present overall design and functionalities. The preamplifier chips for the scintillator pad detector and preshower counter have to cope with the fluctuating pulse shape produced by minimum ionizing particles. The two designs can be made very similar. Prototype chips for the preshower counter were successfully tested with the test beam. The common front-end card for the scintillator pad detector and preshower is similar to the one for the electromagnetic and hadron calorimeters and a first version of its schematic design has been completed.

Muon Detector

The optimization of the muon-system layout is completed, resulting in a reduction of 44% of the logical channels (now 26 000) and 35% of the physical channels (now ~ 150 000) compared with the Technical Proposal. The optimized layout has been used to establish a baseline front-end architecture with a realistic data-flow from the chambers to the Trigger and DAQ system.

Experimental Physics Division 43 From the various chamber technologies investigated in many beam tests, Multi-Wire Proportional Chambers (MWPCs) with anode and/or cathode readout have been chosen for more than half the area of the muon system. In addition, RPCs are selected in areas where the required rate capability is less than 1 kHz/cm2 and where the requirement on cluster size is rather modest.

Special emphasis in this year’s beam tests has been placed on the investigation of front-end chips. It has been shown that for the readout of MWPCs an adapted ASDQ chip allows efficiencies above 95% to be obtained within a 20 ns time window over a plateau of 400 V. The input capacitance was up to 200 pF and an µ Ar(40%)/CO2(50%)/CF4(10%) gas mixture was used. In parallel, CARIOCA, a fast binary 0.25 m CMOS FE-amplifier has been developed, using a novel current-mode technique. The first prototype showed very encouraging results. Since CARIOCA is made specifically for LHCb, a part of the required OR logic can be included in the design. The GaAs and Bari chips, developed for ATLAS and CMS, are under study for the RPC detector. The Technical Design Report of the muon system is scheduled for May 2001.

Trigger

Level-0: muon trigger

The performance and robustness of the trigger has been tested for the different layouts, worst-case noise levels and for luminosities more than twice higher than our nominal running scenario, and found to be satisfactory. Several boards have been prototyped to test the following:

– high-speed optical links with high integration density (1.6 Gbit/s, and up to 20 links/9 U board),

– synchronization protocol,

– use of high density FPGAs,

– point-to-point backplane connections at 480 Mbits/s,

– multipoint connections between up to 16 boards at 40 MHz.

Several of the above aims have already been achieved in preliminary tests.

Level-0: calorimeter trigger

The part of the calorimeter trigger situated on the front-end cards has been defined in detail, and has been fully simulated. The board is being prototyped to confirm the simulation. A technical description of the selection crate has been made.

Level-0: pile-up veto

The efficiency of the pile-up veto has been re-evaluated using the new PYTHIA settings, which describes better the existing measurements. The new generator setting gives a multiplicity distribution that is much wider than that given by the old setting, and the algorithm had to be refined.

44 Experimental Physics Division Level-0: decision unit

The Level-0 decision unit was modelled in VHDL.

Level-1

The network between the front-end boards and the CPU farm was simulated in Ptolemy, leading to the adoption of a 2D-mesh topology using SCI as a test bench. A prototype network has been set up to test the results of the simulation, and to show that the required transaction rate of 1 MHz can be reached. The first results with the 0.5 MHz rate have already been obtained. The algorithm has been coded in C++ inside the LHCb GAUDI framework. The algorithm is now being benchmarked to calculate the size of the farm needed, and the necessary L1 latency. The Technical Design Report of the trigger system is scheduled for January 2002.

Computing

The computing project in LHCb covers both off- and online aspects of the experiment, including the Experiment Control System.

Data Acquisition System

The architecture of the Timing and Fast Control (TFC) system has been revised to allow for more flexible partitioning of the DAQ system. The TFC switches have been specified and designed. The readout supervisor module has been specified, and the design is in progress.

Prototype boards of the readout unit have been produced and commissioning of the functional blocks is now in progress. The protocol between the readout unit and the event builder has been specified.

Studies have started on use of Gigabit Ethernet as the switching fabric of the event builder. Simulation of the full LHCb readout architecture and protocols is now starting. The event-building software is to be implemented to run on intelligent Network Interface Cards (NICs). Performance tests of the NICs have already been completed. The event-building code is now being implemented.

Experiment Control System

LHCb participates actively in the Joint Controls Project (JCOP) with the other LHC experiments and CERN/IT Division. The tendering procedure for the commercial controls software package (SCADA) was completed. The JCOP Architecture Working Group has defined a controls hierarchy, including partitioning rules and the basic alarm handling mechanism.

A single controls framework is being built which has responsibility for configuring the operational environments of the detector (voltages, temperatures, gas pressures, etc.) and of the data-taking system (hardware configuration, run control). A first prototype has been built based on the SCADA software, which includes a finite state machine package and a communication mechanism for accessing non-SCADA

Experimental Physics Division 45 platforms. Investigations have started into the use of commercial credit-card PCs to interface the control system with electronics boards in a radiation-free environment. A prototype is being designed.

Data-Processing Software

All LHCb data-processing applications are being built using the LHCb software framework GAUDI. The latest releases allow simulated events stored in ZEBRA format to be read and new data to be written using an OO persistency tool taken from the ROOT package. Other new components include a structured description of the detector and its geometry based on the XML language, and support for statistical data, e.g. histograms. Work is now in progress to extend the framework in many specialized areas, such as integration with the GEANT4 simulation package, the addition of components for managing calibration and alignment data, the development of a visualization framework and analysis tools.

A new LHCb reconstruction program, called BRUNEL, has been developed. It is based on the OO framework (GAUDI) but uses most of the existing physics algorithms written in FORTRAN. At the same time much effort has gone into developing new algorithms, redesigned using OO methods and written in C++. This new OO code is gradually being incorporated into BRUNEL with the aim of eventually producing a reconstruction program that conforms entirely to an OO design.

Studies have also started to check the ability of GEANT4 to reproduce the results obtained with detector prototypes in the test beam.

Computing Infrastructure

LHCb has participated in the MONARC project, and in the definition of the DataGrid and national GRID projects. As part of the participation in the LHC computing review, an LHCb computing model has been defined to respond to the special needs of the experiment.

Infrastructure in UX Cavern

The counting houses from the DELPHI experiment will be used in LHCb and their arrangement behind the radiation-shielding wall has been determined. The counting house will have room for all racks presently foreseen, including a high safety factor. Platforms for the gas racks will be placed above the two access gates. They will provide space for 24 gas racks in total.

At present the detector assembly close to the interaction point is being studied. As the available space for the RICH-1 and the vertex detector is very tight, a careful study of the different manoeuvres has to be performed.

LHCb has studied the LEP–LHC equipment transfer list and decided which of the available parts of the LEP experiments are useful to acquire. Most of the equipment will come from the DELPHI experiment and a few facilities from ALEPH are planned for the support structure of the LHCb detector.

46 Experimental Physics Division The SPS Fixed-Target Programme

Muon Experiments

NA58

The COMPASS experiment aims at a deeper understanding of nucleon structure and confinement. The main physics observables studied are the polarization of the nucleon constituents of a polarized nucleon, the mass and decay patterns of light hadronic systems with either exotic quantum numbers or strong gluonic excitations, and the leptonic decays of charmed hadrons.

A possible polarization of gluons ∆G in a polarized nucleon is searched for by the study of hard processes in polarized deep inelastic scattering, open charm production and high-pT-meson production. Using very large event samples COMPASS should determine the gluon polarization to an accuracy in ∆G/G better than 0.05 in gluon the kinematical region of x Bj around 0.05–0.3. The flavour-separated spin structure functions of the nucleons in polarized muon–polarized nucleon deep inelastic scattering will also be measured, both with longitudinal and transverse polarization mode. In the latter mode the still unmeasured transverse spin structure function h1(x) will be investigated.

Gluonic degrees of freedom will be excited in hadrons using diffractive and double diffractive scattering. High statistics measurements will allow the mass range above 2 GeV/c2 to be accessed. Leptonic and semileptonic decays of charmed hadrons will be studied using a specialized detector arrangement to identify such processes and discriminate background. Accuracies aimed at are around 10% for f and 20% for f . In D s D addition many soft processes can be studied testing low-energy theorems of QCD.

The COMPASS spectrometer is currently being assembled at the CERN SPS in the muon area. It combines very high rate beams with a modern, two-stage, fixed-target magnetic spectrometer. The design of detector components, electronics and data-acquisition system will allow us to handle beam rates up to 108 muons/s and about 5 × 107 hadrons/s with a maximal interaction rate of about 2 × 106/s. The detector consists of a variable 6 target region allowing the use of a new high-acceptance polarized target (both LiD and NH3 will be used as target materials), an LH2 target or a solid target combined with a high-resolution silicon tracker. Particle tracking will be performed using several stations of scintillating fibres, silicon detectors, micromega chambers and microstrip gas chambers using the GEM technique. Large-area tracking devices will be made from gaseous detectors (planar drift chambers, straw tubes and MWPCs) placed around the two spectrometer magnets. A large-acceptance RICH is used for particle identification up to 60 GeV/c, placed downstream of the first spectrometer magnet. Calorimetry (both, electromagnetic and hadronic) will be installed at the end of each spectrometer section. The readout mostly follows the pipeline principle and requires very fast signal conversion. The DAQ should handle about 105 readouts/s which is sent into an online computing farm for data filtering. About 104 events/spill will be recorded centrally in the CERN Computing Centre, requiring a steady data stream of 35 Mbyte/s.

The different components are currently under construction at the various home institutes of the Collaboration, and most components will be installed during the first half of 2001. A reduced version of the

Experimental Physics Division 47 full spectrometer will be assembled, the so-called ‘initial layout’, capable of measuring at least the gluon polarization ∆G and performing measurements with Primakoff reactions.

A first test run was carried out in 2000, in which an overall test of almost all detector components, the DAQ and the offline system was performed. No major problem was encountered and data could be taken in pipeline mode with most of the detectors included in the readout. A major milestone, the proof of principle of our new readout and DAQ architecture, could thus be reached. A commissioning run is foreseen in the SPS period from July to November 2001, for an overall test of the detector system and tracking performance. We are aiming for a first physics run at the end of this period. The detector for the initial layout should then be completed by spring 2002.

Neutrino Experiments

WA95

The main goal of the CHORUS experiment is to search for neutrino oscillations in the νµ →ντ sector, by detecting the occurrence of the reaction ντN →τX within a large sample of νµ interactions. The τ is mainly identified by its characteristic decay topology, and separated from topological backgrounds by charge and kinematical analysis. This is possible by means of a hybrid detector exploiting the nuclear emulsion technology.

CHORUS took data in the wide-band neutrino beam of the SPS from May 1994 to November 1997. A sample corresponding to about 850 000 νµ charged-current interactions was recorded permanently in the emulsion target and also by the electronic detectors. Events were reconstructed in the electronic detectors and, after kinematical and fiducial volume cuts, 440 606 predictions (mainly νµ charged-current and neutral- current interactions) were measured in the scanning laboratories.

Results were published based on a sample of 166 000 events located in the emulsion. The events were analysed by searching for τ decays into a muon or into a single charged hadron. With the above statistics no τ –4 candidates were found. This observation corresponds to an upper limit P(νµ →ντ)<3.4× 10 at 90% C.L. in 2 2 2 the region above few eV . Full mixing between νµ and ντ is excluded at 90% C.L. for ∆m >0.6eV . This publication is the conclusion of ‘phase I’ of the CHORUS emulsion analysis. The results are shown in Fig. WA95–1.

A new technique, netscan, has been developed to study the interaction vertices of neutrino events. In a volume with an area of 2mm2 perpendicular to the beam and over eight emulsion plates along the beam (6 mm), all track segments stored in the emulsion are measured and used as input to a pattern-recognition procedure. This enables the recognition of secondary vertices created by the decay of neutral and charged particles with much higher efficiency than previously obtainable. A few hundred charm-production candidates have already been found and are being analysed.

At the same time, a new pattern-recognition program has been developed and new predictions have been prepared to be used in the second phase of the analysis. The CHORUS ‘phase II’ analysis will profit from the netscan technique and the new predictions to improve the sensitivity to oscillation and to collect a few

48 Experimental Physics Division thousand charm-production candidates. This phase will require two more years, and is made possible by large advances in the computer-assisted automatic microscope technology which will allow the Collaboration to reconstruct the interactions at unprecedented scanning speed. The automatic scanning technology evolution — involving developments in optics, electronics and software — is headed by the scanning laboratories involved in the CHORUS experiment.

The rare process of J/ψ production via neutrino neutral-current interaction has been observed. The result has been obtained by an analysis of neutrino events originating in the calorimeter of the CHORUS detector. A J/ψ –41 2 spectrum-averaged cross-section σ = (5.8 ± 2.4) × 10 cm was determined for 20 GeV ≤ Eν ≤ 200 GeV. The data favour a significant contribution of excited charmonium states decaying into J/ψ, in qualitative agreement with theoretical expectations.

CHORUS E531 NOMAD CCFR

CHARM II

CDHS

Fig. WA95–1: Present limit on νµ →ντ oscillation compared with the results of previous experiments (dashed lines) and with the recent NOMAD result (full line); the second CHORUS curve (dash–dotted), is obtained using the technique proposed by Feldman and Cousins.

WA96

ν →ν ν →ν NOMAD is an experiment searching for µ τ and µ e oscillations in a neutrino beam consisting predominantly of νµ’s. The data-taking was completed at the end of 1998 and the detector was dismantled during the course of 1999.

During the course of 2000 NOMAD completed its search for νµ →ντ oscillations. ντ charged-current interactions were looked for with the τ decaying to an electron, a muon or hadrons plus the relevant neutrino(s). No oscillation signal was found but the limit set (Fig. WA96–1) is in accordance with the expectations of the proposal, thus demonstrating the validity of the kinematic method used by NOMAD to search for ντ charged-current interactions. This result has been presented at conferences and the final paper is now being written. The same analysis has also enabled NOMAD to set the best limit currently available on ν →ν e τ oscillations.

Experimental Physics Division 49 ) 4

/c 3 2 10 E531 (eV 2 m ∆ CCFR 102

NOMAD 10

ν → ν 1 µ τ

90% C.L. CDHS

10–4 10–3 10–2 10–1 1 sin2 2θ 2 2 Fig. WA96–1: The final 90% C.L. exclusion contour in the ∆m –sin 2θµτ plane established by NOMAD during 2000.

ν →ν The µ e search has reached its final phase with the systematics of the measurement now being evaluated.

In parallel, the fine granularity and good energy and angular resolution of the detector, coupled with the recording of more than a million νµ charged-current interactions, allowed the NOMAD team to complete and publish the following measurements in 2000:

– production of opposite-sign dimuons leading to a measurement of the strange content of the nucleon and of the charm-quark mass;

– search for MeV singlet neutrinos mixing with tau neutrinos;

ρ0 ν – inclusive , f0 and f2 meson production in µ charged-current interactions;

– measurement of the Λ polarization in νµ charged-current interactions.

In addition the following topics have been studied and are now being written up for publication:

– measurement of the antilambda polarization in νµ charged-current interactions;

– backward-going protons and negative pions in νµ charged-current interactions;

– search for neutral heavy leptons.

Further topics still under study include the following:

– strange particles;

– charmed particles;

– Bose–Einstein correlations.

50 Experimental Physics Division CP Violation

The NA48 experiment measures direct CP violation in the decay of neutral kaons into two pions. CP →π+π– → π0 violation was established in 1964 by the observation of the decay KL and subsequently in KL 2 , →π ν →πµν →π+π–γ →π+π– the charge asymmetry in KL e and KL , KL decays, and more recently in KL e+e– decays. All these observations of CP violation are restricted to the neutral-kaon system. They can be explained by the mixing between K0 and K0 states which is characterized by the parameter ε.

On the other hand direct CP violation can also occur in the transition from a CP-odd K0 eigenstate to a 2π final state with even CP. It is characterized by the parameter ε′. The first evidence for direct CP violation was published in 1988 by the NA31 experiment at CERN.

The NA48 experiment compares the decay rates of short- and long-lived K0 into charged and neutral pions, respectively. The parameter ε′/ε is extracted from the double ratio of four event-counts:

Γ()()K → π0π0 / Γ K → π+ π− R = L L ≈1− 6× Re ε'/ ε (1) Γ()()→ π0π0 Γ → π+ π− KS / KS

A non-zero value of Re ε′/ε signals that direct CP violation exists.

The NA48 apparatus consists of two neutral beams: a KL beam from an upstream target and a KS beam from a target close to the decay region. The decay region is followed by a detection system for 2π0 and π+π– final states. In addition, a proton ‘tagging’ system is employed in order to determine from which beam each decay occurred.

The layout of the detector is shown in Fig. NA48–1. The 2π0 events are measured in a liquid-krypton electromagnetic calorimeter with 13 500 readout cells. The π+π– events are detected in a charged-particle spectrometer consisting of four multiwire drift chambers and a magnet of large aperture. A time resolution of 300 ps is achieved in the coincidence of either charged- or neutral-pion decays with a proton in the tagger for

KS and KL identification of the parent particle.

A first measurement of Re ε′/ε by NA48 was based on the data collected in 1997 and was published in 1999. New data taken in 1998 were analysed and a preliminary result was presented this spring.

The table below shows the number of events collected in each channel after removing background and correcting for mistagged events.

Statistical samples (in thousands of events)

→π0π0 →π0π0 →π+π– →π+π– Ye ar K L KS KL KS 1997 489 975 1071 2087

1998 1140 1800 4870 7460

Experimental Physics Division 51 The new result is R = 0.9927 ± 0.0017 (stat.) ± 0.0024 (syst.) which, using Eq. (1), leads to Re ε′/ε = (12.2 ± 2.9 ± 4.0) × 10–4 (preliminary). The systematic uncertainty is determined partially by the statistical contribution of the control samples. The combined result of the first two years of data-taking is, with statistical and systematic errors added in quadrature,

Re ε′/ε =(14.0± 4.3 ) × 10–4.(2)

This measurement confirms that Re ε′/ε is small but non-zero and, therefore, that direct CP violation occurs in neutral-kaon decays. The result is consistent with a recent measurement of (28 ± 4) × 10–4 by the KTeV Collaboration at Fermilab. A comparison of all recent experimental measurements of Re ε′/ε is shown in Fig. NA48–2.

→ π0 × 9 The data collected in 1999 amount to ~ 2 million KL 2 candidates. About 7 10 triggers have been recorded in a volume of 100 Tbyte on tape. Data analysis is well advanced and a result should be available by the time of printing this report.

After completion of data-taking in 1999, a section of the carbon-fibre beam pipe which carries the neutral beam through the detector to the dump had imploded after being in use for two years. As a consequence of this incident, all four drift chambers of the magnet spectrometer were damaged. By the end of 2000 two of the drift chambers had been repaired. It is expected that the experiment will be fully operational again in summer 2001.

A part of this year’s beam time has been used to collect data with neutral final states in an intense KS/hyperon beam.

+ – A future programme of physics in two parts using intense KS and simultaneous K and K beams has been proposed by the Collaboration. This is outlined in Addenda 2 and 3 to the P253 proposal. We refer to these for details of the physics case and the implementation of this programme. In the meantime, both experiments have been approved. MUON CTRS. HODOSCOPE DCH1 DCH2 DCH4 DCH3 FINAL COLLIMATORS SPECTROMETER

KS AKS KL MAGNET VACUUM TANK BEAM MONITOR BEAM DUMP

He GAS ANTI 1 E.M. CALORIMETER HADRON CALORIM. WINDOW KEVLAR ANTI 2 ANTI 3 ANTI 4 ANTI 5 ANTI 6 ANTI7 y=500mm

z=0 10m 20m 30m 40m 50m 60m 70m 80m 90m 100m

Fig. NA48–1: Schematic layout of the NA48 detector.

52 Experimental Physics Division Fig. NA48–2: Summary of Re ε′/ε measurements. The earlier NA31-1986 and E731a values are included in the final NA31 and E731 values, respectively. The horizontal band corresponds to the average of the experimental values.

Heavy-Ion Experiments

NA45-2

NA45/CERES (BNL, CERN, JINR Dubna, GSI Darmstadt, MPIfK Heidelberg, Univ. Heidelberg, INP Rez, Univ. at Stony Brook and WIS Rehovot) is an experiment optimized for the measurement of electron– positron pairs produced in collisions of heavy nuclei at SPS energies. The main goal is to systematically study the pair continuum in the mass region from 0.1 to about 2 GeV/c2 and the vector mesons ρ, ω and φ. The spectrometer covers the mid-rapidity region 2.1 < η < 2.65 and 2π in azimuthal direction. It also has capabilities for hadronic observables with the combined information from the TPC and the silicon drift detectors, and for high-momentum hadrons (γ≥32) by also including the information from the RICH detectors.

The results from the first high-statistics data-taking in 1996 using a Pb beam at the SPS energy of 158 GeV per nucleon were presented in the 1998 Annual Report. The most striking feature is a strong enhancement in the e+e– yield over the expectation from simple extrapolations of pp and pA collisions at masses intermediate between twice the pion mass and the ρ, ω pole. Integrating over the mass window 0.25–0.70 GeV/c2 this enhancement is a factor of 2.8 ± 0.5 (stat.) ± 0.6 (syst.) for moderately central collisions including the most central 1/3 of the geometric cross-section. This enhancement is more pronounced for low pair transverse momenta and has given rise to a large number of theoretical studies. The current understanding is that a modification of the ρ spectral function is required for high baryon densities and temperatures. The modification is possibly linked to the restoration of chiral symmetry close to the phase boundary to the quark– gluon plasma. This is supported by the fact that a description of the data is also possible by a lowest-order perturbative QCD calculation, i.e. using partons only and not hadrons. This calls for a study of the other vector mesons such as ω and φ and also at a beam energy which varies the two-degrees-of-freedom baryon density and temperature.

Experimental Physics Division 53 In the period 1997–1999 CERES completed an upgrade by the addition of a new magnet and a radial TPC downstream of the present spectrometer; this upgrade is intended to give a mass resolution improved by about a factor of 3 compared with the 1996 performance (6.8% at the ω mass).

About 8 × 106 events were taken with the upgraded detector in the 1999 heavy-ion run using a 40 GeV/c per nucleon Pb beam. These conditions should provide a maximum baryon density about 50% higher than at full SPS energy and at the same time a pion multiplicity reduced by about a factor of 1.5. Despite our finding of a stronger than linear scaling with pion multiplicity at a given beam energy — at 158 GeV per nucleon the scaling is consistent with quadratic — one may expect a comparable enhancement.

In 2000 CERES recorded data for 33 × 106 central 158 A GeV/c Pb–Au collisions at a rate of 400 events or 200 Mbyte per 4.5 s burst. Also, 0.5 × 106 events at 80 GeV/c per nucleon were recorded. While for some of the 80 GeV/c data there are already preliminary analysis results for hadronic correlations and fluctuations, the analysis in general has just started. A brief summary of the results from 40 A GeV/c will be given below.

Figure NA45–1 shows the still preliminary result of the 40 GeV/c e+e– measurement together with our expectation from hadronic decays. The total number of e+e– pairs for m > 0.2 GeV/c2 is 159 ± 46 (stat.). This corresponds to a significant enhancement at intermediate masses (integrating the range 0.2–0.9 GeV/c2 yields a factor of 5.9 ± 1.9), comparable with the 158 A GeV/c result. Again the enhancement is dominantly at low pair transverse momenta. The theoretical models with medium modifications of the ρ meson due to high baryon density are consistent with these preliminary data.

CERES/NA45 Pb-Au 40 A GeV Preliminary

1 –5 σ σ ≈ – 10 trig/ tot 30% ) 2

pt > 200 MeV/c

10–6 Θ > 35 mrad η→ ee ee γ ) (100 MeV/c 2.1< η < 2.65

η ω→

/d –7 10 ee

ch π 0

)/(dN η′→ ee –8 ee

10 ee ee γ dm η ω→ φ→ /d ee

N –9

2 10

(d ee γ ee

ρ→ → 0 10–10 π 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 mee (GeV/c ) Fig. NA45–1: Invariant-mass distributions of e+e– pairs emitted in Pb–Au collisions at 40 A GeV/c for the top 30% of the centrality range. Also shown is the hadronic decay background as estimated by CERES (solid line) as well as the various contributions to it (thin lines).

While the statistical significance of the 1999 data is somewhat limited we expect for the 2000 data a signal of several thousand e+e– pairs.

54 Experimental Physics Division First analysis of hadronic observables resulted in yields and spectra of negatively charged hadrons, of the difference between positively and negative charges, and of reconstructed lambdas. Analysis of the correlation function of two identical particles with respect to their momentum difference in three dimensions as a function of centrality and pair momentum clearly indicates strong expansion of the fireball. The freeze-out density in coordinate space and in six-dimensional phase space is found to be the same as at 11 GeV/c, at the full SPS energy and, most recently, at RHIC (s = 130 GeV). Azimuthal charged-particle distributions were analysed and reveal an elliptic event shape with preferential emission of particles in the reaction plane; the second Fourier coefficient is 3–4%. The magnitude appears to systematically increase from 6 GeV/c per nucleon through the SPS energy range up to RHIC energies. An analysis of the fluctuations in pt from event to event indicates small (1–2%) nonstatistical fluctuations.

NA49

The NA49 experiment (Univ. Athens, LBL Berkeley, Univ. Birmingham, Comenius Univ. Bratislava, KFKI Budapest, CERN, INP Krakow, GSI Darmstadt, JINR Dubna, IKF Frankfurt, Univ. Houston, Kent State Univ., Univ. Marburg, MPI Munich, UCLA, INS Warsaw, Univ. Warsaw, Univ. Washington Seattle, Hua Zhong Univ. Wuhan, RBI Zagreb) investigates hadron production in p–p, p–A, and A–A collisions at the SPS. Its high-precision tracking and particle identification in a wide acceptance allows for a unique study of soft hadronic phenomena ranging from the most elementary hadronic interactions over impact-parameter controlled p–A collisions to heavy-ion interactions with different masses and energies.

The experimental set-up comprises mainly two medium-size TPCs (VTPC-1,2 of 3 m3 each) located inside two superconducting vertex magnets, and two large-volume TPCs (MTPC-R,L of 20 m3 each) positioned downstream of the vertex magnets symmetrically to the beam for tracking and particle identification via dE/dx. Highly segmented scintillator TOF arrays complement particle identification. Calorimeters for transverse-energy determination and triggering, a detector for centrality selection in p–A collisions, beam- definition detectors and — since the year 2000 — two Veto Proportional Chambers (VPCs) for detection of neutrons in connection with one of the calorimeters complete the set-up.

In 2000, thanks to the excellent performance of the detector as well as the accelerator complex a total of five million events were registered with a p-, π+-, and π– -beam impinging on a liquid-hydrogen target. This brings the number of p–p events now available for data analysis to 2.4 million. During the Pb-beam period 340 000 events were collected at 80 GeV/c per nucleon thanks to a special effort from the accelerator crews. Due to an optimization of the event registration rate three million events of central Pb–Pb interactions at 158 GeV/c per nucleon could be recorded. Finally 900 000 d–p events were collected by fragmenting the Pb- beam with a carbon converter and selecting deuterons, concluding the extremely efficient data-taking period.

The large number of p–p events allows for the first time the extraction of the cascade particles Ξ– and anti- Ξ+ in this elementary interaction. Fig. NA49–1 (left) shows the yield of these double strange baryons in ±1 unit around mid-rapidity. The large phase-space coverage of the NA49 detector allows for an integration Ξ+ Ξ– over the complete pT range. The ratio anti- to turns out to be 0.5 ± 0.06 at mid-rapidity. In order to connect up to the complex A–A collisions NA49 measures the Ξ– and anti-Ξ+ production also in p–A collisions at different centralities characterized by the mean number of collisions ncoll. For illustration the rapidity distribution of the Ξ– is shown in Fig. NA49–1 (right), revealing an enhanced Ξ– production at lower rapidity for more central p–A collisions (〈ncoll〉 = 5.7) than for less central p–A interactions (〈ncoll〉 = 3.7). This

Experimental Physics Division 55 can be attributed only partially to the different degrees of stopping of the incident proton as a similar behaviour is seen for the anti-Ξ+. The study of the strange cascade particle production in p–p and centrality- controlled p–A collisions is of primordial importance for the understanding of the enhancement of the strange particle production in A–A collisions which in certain phenomenological descriptions is interpreted as the onset of deconfinement, i.e. quark–gluon plasma creation.

Fig. NA49–1: Rapidity distributions of Ξ– and anti-Ξ+ in p–p collisions at 158 GeV/c (left) and rapidity distributions of Ξ– in p–A collisions with different centralities (right).

NA50

The NA50 Collaboration (Annecy, Bucharest, Cagliari, CERN, Clermont-Ferrand, Lisbon, Lyon, Moscow, Orsay, Palaiseau, Strasbourg, Torino, Yerevan) devoted its main effort in 2000 to the collection of a new sample of Pb–Pb interactions at 158 GeV/c per nucleon. The purpose of this special run is to consolidate some peculiar features of charmonium production already established with previously collected data samples and to extend the range of investigation to centrality domains which were previously hard to explore because of specific experimental difficulties. The centrality of the reaction is estimated for each event from the measured neutral transverse energy Et and forward energy EZDC.

From the first sample collected in 1995, the experiment had shown that the J/ψ production yield is strongly suppressed in central Pb–Pb collisions, with respect to the production of high-mass Drell–Yan pairs.

With improved event selection and analysis techniques applied to the high-statistics event sample of 1996, it was inferred that the J/ψ cross-section per nucleon–nucleon collision measured in peripheral Pb–Pb collisions agrees with the ‘normal’ suppression pattern inferred from p–A and S–U measurements. This new analysis also revealed that as the Pb–Pb collisions become more central, the J/ψ production yield shows a significant drop in the Et range between 40 and 50 GeV, corresponding to an impact-parameter interval of χ 7–8 fm. This drop is currently interpreted as being due to the suppression of c production (whose radiative decays are responsible for around 30–40% of the J/ψ yield observed in proton-induced interactions).

56 Experimental Physics Division The analysis of the data collected by the NA50 experiment in 1998, with a much thinner target in order to clarify certain systematic effects relevant to the most central collisions, extended and clarified the pattern of the previously observed J/ψ anomalous suppression. The new measurement provides a deeper understanding of the previous observations and reveals a steady significant decrease in the J/ψ production rate up to the most central Pb–Pb collisions.

In 2000, data were also collected with a thin target, with an improved and redundant trigger system. These qualitative upgrades should lead to an easier analysis of the most central Pb–Pb collisions. Moreover, the Pb– beam vacuum pipe was extended downstream to include the target system itself. The elimination of the pollution due to Pb–air interactions should allow us to explore the most peripheral Pb–Pb interactions and confirm, eventually, their normal behaviour.

The results published up to now, summarized in the detailed pattern of the ‘anomalous J/ψ suppression’ shown in Fig. NA50–1, clearly rule out the presently available conventional (hadronic) models of J/ψ suppression, which predict a saturation of the J/ψ rate for central Pb–Pb collisions. On the contrary and together with the sharp onset of the anomalous suppression previously reported, the new observation leads to a global production rate pattern which finds its natural explanation in the framework of the formation of a deconfined state of quarks and gluons. The results from the data sample of 2000 will allow us to refine some of the past observations of the experiment.

The NA50 experiment also observed a significant excess in the production of intermediate-mass dimuons, in heavy-ion collisions, with respect to the expected sources, Drell–Yan and muon pairs from decays of charmed mesons, which properly explain the p–A data. This excess can be described by an enhanced production of charm. Another possible explanation consists in adding a source of thermal dimuons to the expected yields of Drell–Yan and charm contributions, as can be seen in Fig. NA50–2, where the data sample containing the most central collisions (about 380 participant nucleons) is shown.

1.4

1.2 suppression ψ 1

0.8

0.6

Pb - Pb 1998 with Minimum Bias 0.4 Pb - Pb 1996 with Minimum Bias Pb - Pb 1996 Measured / Expected J/ S - U NA38 0.2 p - A NA38 p - p(d) NA51 0 0 0.5 1 1.5 2 2.5 3 3.5 ε (GeV/fm3)

Fig. NA50–1: Measured J/Ψ production normalized to the expected yield, as a function of the energy density reached in the collision.

Experimental Physics Division 57 105 105 IMR

dN/dM χ2/ndf = 2.8

104

103

1.6 1.7 1.8 1.9 2 2.1 2.2 2.3 2.4 2.5

102 thermal

10 – DD Pb-PbET 7

12345678 2 Mµµ (GeV/c ) Fig. NA50–2: The intermediate-mass dimuon spectra can be well accounted for by thermal radiation, combined with Drell–Yan and open charm.

NA57

The NA57 Collaboration (Bari, Bergen, Birmingham, Bratislava, Catania, CERN, Kosice, Legnaro, Oslo, 0 Λ Ξ– Padua, Prague, Rome, Salerno, St. Petersburg, Strasbourg, Utrecht) studies the production of K S and of , and Ω– baryons and their antiparticles in ultrarelativistic nucleus–nucleus collisions at the SPS.

As first observed by the WA97 experiment WA97 (Fig. NA57–1, closed symbols), while the yields per participant of strange baryons and antibaryons have similar values in p–Be and p–Pb collisions, in Pb–Pb collisions they are instead all clearly above the p–A values. The effect is larger for particles of higher strangeness content, up to a factor ~ 15 for the s = 3 Ω– + Ω+. Such behaviour was predicted long ago (Rafelski and Müller, 1982) as a possible signature of the deconfinement phase transition from standard hadronic matter to a plasma of quarks and gluons. Microscopic hadronic collision models do not reproduce it. Be Be − −  WA97 WA97 Ω− + Ω+

10 NA57 10 NA57 Ξ−

 Ξ+ Λ

– Yield/wound. nucl. relative to p h Yield/wound. nucl. relative to p  Λ 1 1

pBe pPb PbPb pBe pPb PbPb

110102 103 1 10 102 103 〈 〉 〈 〉 Nwound Nwound Fig. NA57–1: Yields per wounded nucleon relative to the p–Be yields from NA57 (only Ξ– and Ξ+, open symbols) and WA97 (closed symbols).

58 Experimental Physics Division The main goal of NA57 is to investigate the existence of an onset for this strangeness enhancement effect at the variation of the energy and centrality (i.e. number of participants) of the nucleus–nucleus collisions. The apparatus consists of a telescope of silicon pixel (about 1.1 million channels) and silicon microstrip detectors and of a set of multiplicity detectors. Data have been collected at both 160 (1998, 2000) and 40 A GeV/c (1999).

In the course of 2000,

– the data-taking at 160 A GeV/c was completed with the collection of 230 million Pb–Pb events, which doubles the NA57 statistics at this energy,

– the reconstruction of the 40 A GeV/c data samples was completed (60 million p–Be events + 290 milion Pb–Pb events),

– the data from the 1998 160 A GeV/c sample were analysed in order to extract the values of hyperon yields.

Figure NA57–1 shows the yields per participant (wounded) nucleon (open symbols) relative to the p–Be yields, in five classes according to the number of wounded nucleons, i.e. the centrality of the collision. In the common centrality range, the yields from the two experiments agree to within about 20%, the NA57 yields being larger. The reasons for this systematic difference are being investigated.

In the new low-centrality bin the Ξ+ (Ξ–) yields, as measured by NA57, drop by a factor of 2.6 (1.3), corresponding to a 3.5 σ (1.8 σ) effect, suggesting an onset for the enhancements when the collision involves between 50 and 100 nucleons. Such an onset may signal the point of the deconfinement phase transition. This urges us to look at the full set of enhancements, as in WA97. The study of the enhancement pattern for Λ, Λ, Ω– Ω+ 0 , and K S is under way.

NA60

The study of high-energy heavy-ion collisions is at present a very active field in particle physics: RHIC has been in operation at BNL since last summer and the ALICE experiment is preparing for such physics at LHC energies. The first goal of this experimental programme, which started in 1986, is the discovery of the phase transition from confined hadronic matter to deconfined partonic matter, predicted by Lattice QCD calculations to occur when the system exceeds a given critical threshold in energy density or temperature. The proof of existence of this phase and the study of its properties are key issues in the understanding of confinement and chiral symmetry.

When this new state of matter was postulated, some signatures of its formation in high-energy nuclear ψ χ ψ′ collisions were proposed. Among these were the suppression of charmonia states (J/ , c and ) — due to the screening of the cc binding potential in the QGP colour soup — and the production of thermal dileptons, electromagnetic radiation emitted by the free quarks. The centrality dependence of the J/ψ suppression pattern, as measured by the NA50 experiment, gives compelling evidence for the existence of a new, deconfined state of matter in which quarks roam freely. Another exciting observation of NA50 is the enhancement of intermediate-mass dimuon production, a possible indication of thermal dimuons.

Experimental Physics Division 59 The NA60 Collaboration (Bern, Bratislava, BNL, Cagliari, CERN, Clermont-Ferrand, Lisbon, Lyon, Orsay, Torino, Yerevan) is setting up a recently approved SPS experiment that will take data with proton and heavy-ion beams between 2001 and 2003, extending the NA50 physics capability.

The NA60 detector complements the muon spectrometer and zero degree calorimeter already used in the NA50 experiment with two new silicon detectors, placed in the target region: a beam tracker and a silicon pixel telescope. The beam tracker is made of four radiation-hard silicon microstrip detectors operated at 130 K. It measures the transverse coordinates of the impact of incident ions on the targets with a precision of the order of 20 microns, allowing the identification of the interaction point with sufficient accuracy to measure the offset of the muon tracks. The 10-plane silicon pixel telescope, of almost one million channels, is placed in a 2.5 T dipole field, vastly improving the dimuon mass resolution, as already shown in beam tests (see Fig. NA60–1).

90 90

80 80 dN/dM

70 70

60 60

50 50

40 40

30 30

20 20

10 10

0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 0.2 0.4 0.6 0.8 1 1.2 1.4 M (GeV) Fig. NA60–1: Dimuon mass distribution measured in p–Be collisions with successful track matching, before (left) and after (right) using the track parameters provided by the pixel vertex spectrometer.

Thanks to these detectors, NA60 will be able to separately study the production of prompt dimuons and of muons originating from the decay of charmed mesons, in proton and ion collisions, thereby clarifying whether the origin of the dimuon excess seen in the intermediate-mass region is due to thermal dimuon production.

NA60 will also measure the yield of charmed mesons and the pattern of J/ψ and ψ’ production in collisions of indium nuclei. These observations will test the present evidence that the deconfined quark–gluon phase sets in at SPS energies, and will provide critical information on the physical mechanisms driving the phase transition. Furthermore, low-mass dimuon data with high statistics and good mass resolution will be collected to study the production of the ρ, ω and φ mesons, and to clarify the striking observations of the CERES experiment that may signal the approach to chiral-symmetry restoration in heavy-ion collisions.

The rebirth of the heavy-ion physics programme at CERN will certainly give a significant contribution to the understanding of the existing results, and considerably help in building a convincing logical case that establishes beyond reasonable doubt the formation of a deconfined state of matter in heavy-ion collisions at the SPS.

60 Experimental Physics Division Channelling Experiments

WA103

The objective of the WA103 experiment is to measure the enhancement in positron production when the incident electron beam is in channelling conditions in a crystal. For such orientation, the number of radiated photons along the major axes of the crystal is much higher than in the amorphous target of the same thickness. Correspondingly, the number of pairs due to the photon materialization is also larger. Tungsten crystals 4 and 8 mm thick are used.

The main physics observables studied are the emission angle and the momentum of the positrons. These quantities are needed to determine the phase space of such positron sources for a comparison with the conventional ones in the framework of a possible use in future e+e– linear colliders. The experiment uses multi-GeV secondary electron beams of the SPS. The electrons, after passing through profile monitors and counters (trigger) impinge on the targets with energies from 5 to 40 GeV (mainly at 10 GeV). Photons as well as e+e– pairs are produced in the targets. These particles come mainly in the forward direction and travel across the magnetic spectrometer, consisting of the drift chamber and positron counters inserted between the poles of a spectrometer magnet. This spectrometer is optimized to analyse the energy and angle of the positrons in the useful range [5–80 MeV]. Photons as well as high-energy charged particles go through the spectrometer and emerge at a small angle. The charged particles are swept out by a second magnet whereas the photons continue on to a detector made of two preshowers and one calorimeter.

The main part of the detection system is the positron detector: a drift chamber (DC) filled with a gas mixture [He (90%), CH4 (10%)] and partially immersed in a magnetic field. The first part of the DC mainly escapes the magnetic field: this facilitates the determination of the emission angle. The second part of the DC is subjected to the magnetic field and allows the determination of the positron momentum. The track reconstruction, for the positrons, will provide the precise values for these two observables. However, a rapid and almost unambiguous indication of the yield and momentum is given by the positron counters mounted on two lateral walls of the DC. They provided, with the photon detectors, the first results on the behaviour of the crystalline targets and permitted some comparison with the amorphous targets of the same thickness.

The data gathered from this experiment allowed us, when using a simplified reconstruction procedure in the DC, to observe the following.

– An enhancement in the production of both photons and e+e– pairs, when the beam direction is aligned with the 〈111〉 axis, with respect to the random conditions; this enhancement was found in the number of tracks reconstructed as positrons. At 10 GeV, for the incident beam, this enhancement is about 2 for an 8 mm hybrid target, made of a 4 mm crystal and a 4 mm amorphous disc, and 3 for the 4 mm crystal.

– An enhancement also in the number of soft positrons (E+ < 80 MeV), as measured on the lateral counters.

– A dependence of photon and pair production on crystal thickness and incident energy as expected by the theoretical predictions. At 40 GeV, the enhancement (on axis) is three times that at 10 GeV for an 8 mm crystal, i.e. a factor of 6 with respect to the random direction.

Experimental Physics Division 61 These first results obtained at different energies are in large agreement with the simulations and consistent with the theoretical predictions. Some of the results are presented in Fig. WA103–1.

Fig. WA103–1: Positron yield as observed on the ‘low-energy’ counter for an 8 mm W crystal. The 〈111〉 axis corresponds to the 1.5 degree position. The electron incident energy is indicated on the curves.

A complementary run will be requested for 2001: The objective is to collect data at a relatively low incident energy (6 GeV), which is one of the options for the positron sources dedicated to the linear colliders. The statistics collected at low incident energy in 2000 were too poor. Some observations will also be carried out at high energies (20–60 GeV) to check the enhancement in pair production associated with the strong fields along the crystal rows.

CNGS Programme

CNGS1

The OPERA experiment is designed for the direct observation of ντ appearance from νµ →ντ oscillations in the CNGS long baseline beam from the CERN SPS to the Gran Sasso Laboratory. The recent measurements of atmospheric neutrino fluxes performed by the Super-Kamiokande experiment indicate a deficit of muon neutrinos and an anomaly in their zenith angle distribution, consistent with νµ →ντ oscillations with ∆m2 ≈ 1.6 ÷ 4 × 10–3 eV2 (90% CL) and full mixing. The Soudan2 and MACRO experiments also made observations compatible with this result. Therefore, the primary goal of OPERA is to obtain direct evidence for ντ appearance, which would confirm the oscillation hypothesis.

A long baseline of 732 km is used between the neutrino source (the CERN beam line) and the detector (located in the underground Gran Sasso laboratory) in order to be sensitive to the oscillation parameters indicated by the Super-Kamiokande data. The CNGS neutrino beam has been optimized for the detection of ντ charged-current (CC) interactions and provides an average νµ energy of about 20 GeV. For the evaluation of

62 Experimental Physics Division the performance of the experiment an integrated fluence of 2.25 × 1020 protons on target is assumed, corresponding to a 5-year SPS operation in a shared mode.

The main principle of the ντ search is the direct detection of the decay of the τ lepton produced by CC interactions. This is achieved by a massive (about 1800 t) neutrino target based on the ECC design which combines, in a sandwich-like cell, the high-precision tracking capabilities of nuclear emulsions (two 50 µm layers on both sides of a 200 µm plastic base) and the large target mass provided by lead plates (1 mm thick). This technique has been recently demonstrated to be effective for τ detection by the DONUT Collaboration.

The basic element of the target structure is the brick, composed of a consecutive series of individual cells with transverse dimensions of 10.2 × 12.7 cm2. Bricks are arranged into planar structures (walls), which are interleaved with electronic tracker planes. The main purpose of the electronic target tracker is to localize the particular brick in which the neutrino interaction occurred, once an interaction trigger is recorded. This brick is then extracted for the emulsion development and scanning in a quasi-online sequence. Large emulsion areas can be scanned with automatic microscopes equipped with fast track-recognition processors. This allows the measurement of both track momenta from their multiple scattering in the brick and electron and gamma energies from shower development.

The target and the tracker sections are further arranged into three independent supermodules (Fig. CNGS1–1). Each supermodule is followed by a downstream muon spectrometer. A spectrometer consists of a dipolar magnet made of two iron walls, interleaved by pairs of vertical drift tube planes. Planes of RPCs are inserted between the magnet iron plates to allow a coarse tracking inside the magnet and a measurement of the stopping particles from the upstream supermodule.

Fig. CNGS1–1: Schematic view of the OPERA detector.

The OPERA design is optimized to achieve low background levels for the τ appearance search. The experiment aims at the analysis of all single-prong τ decay modes (e,µ,h). Signal events are classified as long or short decays depending on whether the τ track traverses an emulsion sheet or not. The main background sources are charm production in CC interactions, hadronic interactions in lead and large angle muon scatterings. These events are rejected by the identification of the primary lepton in CC interactions and either

Experimental Physics Division 63 by requiring the presence of a τ-like kink topology (long decays) or by an impact parameter method (short decays). In addition, a kinematic analysis can be used to enhance the signal to background ratio. Overall, a total background of about 0.6 events is expected. If νµ →ντ oscillations occur, the average number of detected signal events ranges from about 5 at ∆m2 =1.6× 10–3 to 30 at ∆m2 =4.0× 10–3 (full mixing). The achieved sensitivity at 90% C.L. is shown in Fig. CNGS1–2 and covers the region of the parameter space allowed by the Super-Kamiokande data. Within this region, the probability to obtain a statistical significance on the detected signal of at least 4σ (Gaussian equiv.) is 92% after a 5-year run. )

4 1 /c 2 (eV 2 m ∆

10–1

–2 10 SUPER-K 90% CL ν 2000

νµ → ντ 90% C.L. 10–3 10–2 10–1 1 sin2 2θ

Fig. CNGS1–2: Sensitivity of the OPERA experiment to νµ →ντ oscillations for 5 years of CNGS running (2.25 × 1020 pot), defined as the average 90% upper limit obtained, in the absence of a signal, by an ensemble of experiments. The region allowed by the analysis of Super-Kamiokande data (neutrino 2000) is also shown.

The OPERA Collaboration includes about 150 physicists from 32 institutes. The experiment has been recently approved as CNGS1 and the first prototypes are being constructed. The start of data taking is scheduled for May 2005.

East Hall Programme

PS212

The purpose of the DIRAC experiment is to determine the difference between the isoscalar and isotensor ππ π+π− S-wave scattering lengths from a measurement of the lifetime of an exotic atom (A2π). One aims at an − improved relative precision from its present value of 20% to 5%. An accurate measurement ofa 0 a 2 will submit the current understanding of chiral symmetry breaking of QCD to a crucial test, and provide information about the value of the two-flavour quark condensate.

64 Experimental Physics Division + − The DIRAC experiment is a double-arm magnetic spectrometer designed to measure π π pairs of low invariant mass. The apparatus was commissioned at the end of 1998 and, since then, has been collecting useful data. Compared to the previous year several improvements have been accomplished before the beginning of 2000 data taking including:

– all four planes of MSGC were in place and took data;

– a new collimator added upstream of the spectrometer magnet provided a ~30% reduction of the background flux coming from secondary particles travelling along the primary proton beam;

– an additional trigger level (level 4) was implemented to select events with at least one track in each arm using the information from the Drift Chamber system;

– new-high capacity VME memories were installed to increase data storage capability;

– some important modifications to the front-end electronics architecture were made to increase reliability and homogeneity of readout system;

– new, faster charge integrators were installed on the Ionization Hodoscope;

– a reconfiguration of the Vertical Hodoscope geometry was performed in order to reduce the geometrical inactive areas (detector slabs interspacing);

– modifications were made to the Muon Detector including a new plane of scintillating detectors and new front-end electronics with TDC, mean timer, and CFD.

During the 5.5 months of data taking, the experiment operated at an average primary proton intensity of 1011 protons/spill (spill length = 400 ms). In this condition, the DAQ system was able to perform at a rate of ~1700 triggers/spill, and accept up to four consecutive spills per machine super-cycle, spaced by 0.5 s. In standard running conditions the experiment collected atomic pairs coming from the ionization of A2π atoms at − + − a rate of ~5 × 10 3 per spill (or ~3 atomic pairs per 106 π π triggers). In parallel the experiment collected + − − samples of e e pairs, π p from Λ decays and charged πππ final states for the calibration of the set-up. The − rate of reconstructed Λ→π p decays in the apparatus was ~0.5 Λ per spill, and a total sample of ~105 Λ particles is available from the 2000 statistics.

The main information about the 2000 data taking is summarized in the Table below. Summary of the data collected during the 2000 run

Target (thickness) Protons per spill Interactions in target per spill π+π− triggers

Ni (95 µm) 1011 6.4 × 107 630 × 106

Ti (251 µm) 7 × 1010 6.3 × 107 240 × 106

A preliminary analysis of data collected in 1999 and in 2000 has shown good set-up performances and excellent momentum resolution. The experimental resolution on the Λ mass peak is better than all previous measurements reported in the PDG.

+ − Evidence of an increased yield of highly correlated π π pairs at low relative momentum (Q < 5MeV/c) is π+π− shown in Fig. PS212–1. There is a strong enhancement of pairs with QL < 5 MeV/c. Coulomb

Experimental Physics Division 65 interaction in the final state is responsible for such enhancement. At very low Q values (Q < 3MeV/c) the data + − show an excess of the number of π π pairs with respect to the expected number of Coulomb and non-

Coulomb pairs (Figs PS212–2 and 3). Such pairs (atomic pairs) originate from the ionization of A2π in traversing the target material.

N 2250 2000 1750 1500 1250 1000 750 500 250 0 -40 -30 -20 -10 0 10 20 30 40 Q (MeV/c) N L 2250 2000 1750 1500 1250 1000 750 500 250 0 -40 -30 -20 -10 0 10 20 30 40 QL (MeV/c) π+π- Pairs

Fig. PS212–1: The distribution of the longitudinal component of π+π− relative

momentum (QL) for time-correlated free (above) and accidental (below) pairs. Events come from the 1999 Pt-target data sample.

0 0 2.5 5 7.5 10 12.5 15 17.5 20 22.5 F Correlation Function Fig. PS212–2: The experimental and predicted correlation functions, defined as + − the ratio between the distributions of free and accidental π π pairs. The excess at low-F (low-Q) is the signal from atomic pairs. Events come from the 1999 Pt- target data sample. The dimensionless variable F is defined as F = ()()()Q / σ 2 + Q / σ 2 + Q / σ 2 . L QL X QX Y QY

66 Experimental Physics Division N

200 Atomic Pairs (F<2)=132 ± 41 Atomic Pairs (F<3)= 282 ± 73 150

Number of Trigg. = 54*106

100

-50 0 5 10 15 20 25 30 F Effect

Fig. PS212–3: Difference between observed dN/dF and predicted dNfree/dF from 1999 Pt-target data.

PS213

The nTOF project aims to measure neutron cross-sections over a wide energy range, 1 eV

The scientific programme concentrates on the following aspects:

– In nuclear astrophysics an extended library of neutron cross-sections is required to describe the synthesis of the chemical elements by neutron capture reactions, i.e. in the Big Bang, in Red Giant stars, and in supernovae. Many of these data, particularly for unstable isotopes, are still missing.

– The design and operation of Accelerator Driven Systems (ADS) has to be based on a set of reliable neutron cross-sections for the spallation target, the structural materials, and for the nuclear fuel itself. Most of the present ADS proposals are oriented to nuclear waste transmutation and use a transuranic rich fuel and fast neutron spectrum, resulting in the need of data not currently available. In these technologies new isotopes (mainly transuranics or from the thorium cycle) play an important role in the core neutronics. In addition, the energy range from keV to several MeV is the most important for the ADS behaviour (different from present nuclear reactors of thermal neutron energies) and finally (n,2n) and fast fission have also a larger impact because of the spallation neutron source. Measurements of

Experimental Physics Division 67 these isotopes, energy ranges, and reactions are urgently required by the industries and research organizations designing ADS devices and nuclear waste management strategies.

– Fundamental questions in nuclear fission have been raised with respect to the role of shell and pairing effects, the fine structure of the potential energy surface, and high- and hyper-deformations over a wide range of nuclear temperature. Many of these physics aspects will be addressed in detailed, high- resolution studies of the fission barrier through a series of fission cross-section measurements.

The Collaboration has dedicated a big effort to the investigations needed for the beam design including aspects of the neutronic properties of the neutron target, beam optics, and the necessary shielding elements. The experimental area has been optimized in order to keep background levels as low as possible. Considerable work has also been invested in the design and construction of the necessary monitor, fission, and capture detectors including such innovative developments as Micromegas, parallel plate avalanche counters, a total absorption calorimeter, liquid noble gas modules, and photosensitive materials. A highly innovative solution was also found for the data acquisition system, which is based on 1 GHz flash ADCs. A detailed technical description can be found in the Technical Report of the nTOF Collaboration, CERN/INTC/2000–018 (Nov. 2000).

During the year 2000, the construction of the nTOF installation has progressed, completing the neutron beam line to the experimental area. The measurements performed during the two weeks of commissioning of November 2000, with low-intensity proton beam, show that the neutron beam intensity and energy profile behave as expected (within the experimental energy range and precision). Detector commissioning and the first physics runs are expected for spring 2001.

The experiment is partially supported by a contract with the EU, within the 5th Framework Programme of R&D in the nuclear waste area.

PS214

The HARP (PS214) experiment will carry out, at the CERN PS, a programme of measurements of secondary hadron production, over the full solid angle, produced on thin and thick nuclear targets by beams of protons and pions with momenta in the range 2 to 15 GeVc.

The first aim of this experiment is to acquire adequate knowledge of pion yields for an optimal design of the proton driver of a neutrino factory. The second aim is to reduce substantially the existing ~30% uncertainty in the calculation of absolute atmospheric neutrino fluxes and the ~7% uncertainty in the ratio of neutrino flavours, required for a refined interpretation of the evidence for neutrino oscillation from the study of atmospheric neutrinos in present and forthcoming experiments.

The experiment comprises a large-acceptance, charged-particle, magnetic spectrometer of conventional design, located in the East Hall of the CERN PS and using the T9 tagged charged-particle beam. The main detector is a cylindrical TPC inside a solenoid magnet which surrounds the target. Downstream, the TPC is complemented by a forward spectrometer with a dipole magnet. The TPC, together with the forward spectrometer, ensures nearly full 4π coverage for momentum measurement. The identification of charged

68 Experimental Physics Division secondary particles is achieved by dE/dx in the TPC, by time-of-flight, by a threshold Cherenkov detector, and by an electromagnetic calorimeter. The set-up is shown in Fig. PS214–1.

After the experiment’s approval in February 2000, the refurbishing of equipment from earlier experiments, and the construction of new equipment started. In October 2000, the milestone of a Technical Run with about half of the equipment already active, was successfully passed. The experiment will take data throughout 2001.

drift chambers time-of-flight scintillators beam-muon identifier

electron identifier

TPC + RPCs in solenoid magnet

threshold Cherenkov dipole magnet

beam Fig. PS214–1: Layout of the HARP experiment.

AD Programme

AD1

The long-term goal of the ATHENA/AD-1 experiment at the Antiproton Decelerator (AD) is a direct comparison of the properties of antihydrogen and hydrogen atoms, by using spectroscopic methods developed for the study of the hydrogen atom. In the initial phase of the experiment, the basic techniques needed to produce slow antihydrogen atoms will be explored and optimized. These techniques include the capture and cooling of antiprotons from the AD, the accumulation of a large number (~108) of positrons in less than a minute, and the recombination of antiproton–positron plasmas in a specially designed electromagnetic trap system. Phase 2 will then be devoted to a systematic study of these atoms.

In 2000, the installation and commissioning of the ATHENA apparatus was completed. Per AD shot of 107 antiprotons, about 15 000 antiprotons were trapped and subsequently cooled in the capture trap. The positron accumulator delivered 4 ×106 positrons per minute, using a 5 mCi Na-22 source. A large fraction of the accumulated positrons were then transferred into the recombination section. The antihydrogen detector − was installed and tested under realistic conditions (3 Tesla, 100 K, 10 7 mbar). The performances are close to the design values; for charged particle detection: spatial resolution ~ 100 micron in r-ϕ and 0.7 mm in z, energy resolution for 511 keV gammas 8.3% FWHM.

Experimental Physics Division 69 In 2001, the design values for antiproton and positron accumulation will be reached by achieving: a) a higher antiproton capture efficiency (factor 2–3), b) a higher positron accumulation rate by using a stronger Na-22 source (×10) and by optimizing the accumulation process (×2). The main experimental goals are the production of slow antihydrogen atoms and the understanding of the dependence of the recombination process on plasma densities and temperatures.

AD2

The Antihydrogen TRAP Collaboration (ATRAP) seeks to do precise laser spectroscopy of antihydrogen. Comparisons of antihydrogen and hydrogen atoms should provide the most stringent test of CPT invariance involving baryons and leptons.

ATRAP is an expansion of the TRAP Collaboration that developed the techniques to take CERN antiprotons from an energy of 6 MeV (momentum 100 MeV/c) all the way down to thermal equilibrium at 4 K for storage. This storage energy is lower than realized previously by more than ten orders of magnitude. The TRAP techniques include slowing, capturing, electron cooling, and stacking of antiprotons. ATRAP and other collaborations will use antiprotons from the Antiproton Decelerator (AD). This new facility makes sense for such experiments because we showed that antiprotons can be accumulated in a trap at much lower expense than was required in the earlier CERN AC–AA–LEAR complex. In the closest approach yet to the production of cold antihydrogen, collaboration members were able to confine cold antiprotons and positrons together for the first time, and to observe their interaction.

ATRAP now includes members who have pioneered crucial techniques required for the study of cold antihydrogen such as the laser spectroscopy of hydrogen, the spectroscopy of trapped hydrogen, atom trapping and laser cooling. Very recently we have demonstrated the first continuous source of Lyman alpha radiation (developed to facilitate antihydrogen spectroscopy) and have demonstrated that the stripping of high Rydberg states of positronium is an efficient way to produce the cold positrons needed for antihydrogen production.

During 2000 ATRAP trapped, cooled, and stacked the first cold antiprotons at the AD, and simultaneously accumulated the first cold positrons. ATRAP also observed the first positron-cooling of antiprotons, the closest approach yet to cold antihydrogen.

AD3

Atomic Spectroscopy And Collisions Using Slow Antiprotons (ASACUSA) is a collaboration between a number of Japanese and European research institutions. During a few short months of AD experimentation in 2000, ASACUSA achieved several of its first-phase AD objectives. Six atomic transitions of the metastable antiprotonic helium atom pHe e were detected by resonating high precision laser beams with these atoms, created when the AD antiproton beam was stopped in helium gas just above its liquefaction temperature. Among the three of these that were previously unobserved, two are in the UV region of the spectrum. Together, these results constrain any difference between the antiproton and proton charges and masses by a further factor of eight relative to the values obtained by the PS205 Collaboration at LEAR.

70 Experimental Physics Division In a further development, encouraging results were obtained in the attempt to bring one microwave and two optical beams to resonance with the pHe e atoms. The objective of these experiments is to measure the hyperfine structure associated with the magnetic interaction between the electron spin magnetic moment and the orbital magnetic moment of the antiproton. Closer study of this highly unusual HFS structure in 2001 may lead to a further CPT test for the antiprotons.

The second-phase ASACUSA programme has also been progressing well. A decelerating radio frequency quadrupole (RFQD) constructed for Tokyo University by CERN PS Division was first tested in a proton beam in Aarhus before being installed at the AD. In November 2000 it reached its design energy in the tens of keV range, with deceleration efficiency close to the expected value. The Aarhus group was then able use the RFQD beam to produce extensive new data on the antiproton stopping power (dE/dx) of carbon, gold, and nickel in the crucial unexplored region between 60 keV and 8 keV.

Meanwhile, the apparatus for the third phase of ASACUSA experimentation has been completed in Tokyo. This phase involves collecting samples of antiprotons from the RFQD in a multi-ring electrode trap and re- accelerating them to produce monochromatic eV beams. Installation of the trap at CERN is now under way and it is expected that the first experiments will be carried out with it in summer 2001. The object of these experiments is to study the formation process of antiprotonic atoms, including a metastable variety of protonium, (p–p). It may also form the basis of new experiments to be proposed on antihydrogen production and spectroscopy.

The ISOLDE Programme

ISOLDE Technical Developments

IS343

The 2 mm thin foil tantalum target that was reported last year is now available as a ‘standard’ ISOLDE target. Recent runs have yielded even greater beams of 12Be and 14Be, but the performance fell off after a day or two. This is thought to be due to overheating and coalescence of the foils.

A new 2 mm foil target is being prepared that will have faster effusion. It consists of a stack of 0.3 cm squares of tantalum foil, spaced apart by 50 mm, and held in an open-sided structure of four tungsten wires as shown schematically in Fig. IS343–1. Also, the ionizer is being enlarged in diameter to speed its effusion. These changes are expected to increase the yield of the short-lived isotopes, with decay times of <100 ms, by a factor of 3–10.

The main delay in the target is due to the diffusion from the foils, but making the foils thinner, whilst maintaining the gaps, reduces the amount of material in the target and so reduces the yield. Nevertheless, it is planned to make a further target from 0.5 mm thick tantalum foils to show that the target has the calculated release characteristics. The yield will be as previously, although the speed will be much improved and the mass decreased by a factor of 4. If the measurements agree with the theoretical model of the release, then it will be possible to design targets with more idealized geometries. The 0.5 mm foils may be made

Experimental Physics Division 71 smaller ~0.1 cm diameter, but spaced more closely to improve the target mass, while maintaining fast diffusion and effusion.

Ionizer, enlarged diameter

Standard ISOLDE tantalum target tube, 2 cm diameter, 15 cm long, 0.5 mm thick wall

Tungsten support wires

Tantalum foils, 2 mm thick, 0.3 cm square, spaced apart 50mm

Fig. IS343–1: Schematic cross-section through the target and ionizer.

IS347

The goal and objectives of REX-ISOLDE are the post acceleration of radioactive ions from ISOLDE to target energies between 0.8 and 2.2 MeV/u and the delivery of beams with small emittance to two target stations (Fig. IS347–1). In order to test a new technology of charge multiplication and post acceleration, experiments with light neutron rich nuclei using Coulomb excitation and neutron transfer reactions are planned using the MINIBALL detector array. In addition, scattering experiments with halo nuclei are planned using the second beam line of the REX-ISOLDE set-up. The linac consists of a radio frequency quadrupole (RFQ) accelerator, which accelerates the ions up to 0.3 MeV/u, an interdigital H-type (IH) structure with a final energy between 1.1 and 1.2 MeV/u, and three seven-gap resonators, which allow the variation of the final energy between 0.8–2.2 MeV/u.

ISOLDE HV platform back to ISOLDE MINIBALL 60 k V beam main beam line detector 60 keV array PENNING Trap Re-buncher 7-gap resonators Separator EBIS IH- A/q<4.5 (q/A)/(q/A)= RFQ st ru cture 1/150 second HV platform beam line 20-60 kV 5 k eV/u 300 keV/u 1.1-1.2 MeV/u 0.8-2.2 MeV/u Fig. IS347–1: Schematic lay-out of REX-ISOLDE.

Except for the IH-structure, all cavities of the linac were installed (Fig. IS347–2) in 2000 and a first test of the charge breeder, the achromatic mass separator, and the RFQ was made in a REX-ISOLDE test beam time. Trapping tests with stable isotopes ranging from 7Li up to 181Ta were carried out in order to verify the REXTRAP performance over a large mass range. Efficiencies of up to 30% for ISOLDE beams and 50% for beams from the test ion source could be reached. In addition, the beam transfer line towards the EBIS was tested and full transmission for a 60 keV K beam could be reached. Beams of rest-gas ions were extracted from the EBIS and characterized. The peak current of the extracted pulse varied between 20 and 300 mA

72 Experimental Physics Division depending on the selected breeding and/or extraction time. The rest-gas beam was analysed in the mass separator and the presence of hydrogen, oxygen and carbon, but also of some nitrogen was clear. Some neon peaks appeared as well since the Penning trap was operated with neon as buffer gas and the differential pumping system in the transport line was incomplete. The beam behaviour in the mass separator is as predicted by the design calculations with COSY infinity reaching a q/A-resolution of about 100.

In the test beam time for the injection of ions from the trap into the EBIS, two types of ions were used: 39, 41K produced in a surface ion source locally supplying ions to the REXTRAP and radioactive 26Na

(t1/2~1s) produced at ISOLDE. Ions from the trap could be detected on the anode of the EBIS electron gun, when the electron beam was switched off. Because of the low beam intensity the trap can provide (5 pA) and a missing beam observation system in front of the EBIS, no charge-bred ions were detected after the mass separator on that occasion. The expected intensity of charge-bred ions in one charge state was about 0.5 pA which was almost the background level. With a new test ion source, we can increase the current of injected ions into the EBIS which allows a better detection of charge-bred ions. In the test beam time the transmission and the final energy of the beam out of the RFQ have been determined as well. After optimization of the injection quadrupole lenses of the RFQ a transmission of 90% could be reached. The energy spread and the total energy of the ions could be determined with a scattering set-up using silicon detectors. The results are comparable within an accuracy of ±1.5% with the measurements already done in Munich. The beam quality delivered to the other structures of the linac is as good as designed.

Fig. IS347–2: Photograph of the REX-ISOLDE linac (left) and of the charge breeder which consists of the Penning trap, the beam transfer line the EBIS and the mass separator.

Experimental Physics Division 73 Nuclear Physics

IS302

The Penning trap mass spectrometer ISOLTRAP (a CERN, GSI, Montreal, München, MSU, Orsay, Jyvaskylä Collaboration) at ISOLDE/CERN provides mass measurements of short-lived nuclides with very high accuracy. Accurate experimental mass values serve for testing nuclear models, help to increase their prediction power for nuclides far from stability, and can reveal nuclear structure. Additionally, some mass values represent important input parameters for Standard Model tests and astrophysical calculations.

The ISOLTRAP Penning trap mass spectrometer consists of three main parts:

– a linear gas-filled radio-frequency quadrupole (RFQ) trap for retardation, accumulation, cooling and bunched ejection at low energy;

– a gas-filled cylindrical Penning trap for further cooling and isobaric separation;

– an ultra-high vacuum hyperboloidal Penning trap for isomeric separation and the actual mass measurement.

ω ⋅ The mass measurement is performed via the determination of the cyclotron frequency c =q/m B of the ion with mass m and charge q revolving in the magnetic field of the strength B. The accuracy of the measured − mass values is typically δm/ m = 1 ⋅ 10 7.

Six radioactive beam times were carried out in 2000. In the first beam time an uranium carbide target was used in conjunction with the resonant ionization laser ion source (RILIS) to measure the mass of neutron-rich tin isotopes. The isotopes 128,129,130,132Sn were investigated.

In particular, the mass of the doubly magic 132Sn is of interest for astrophysical calculations along the r- process path.

The second beam time was dedicated to neutron-deficient Sr isotopes. The mass of 76Sr and 77Sr could be 76 measured by determining the mass of SrF2 molecules. Sr is a possible waiting point on the astrophysical rp- process path.

One major project in 2000 was the measurement of the Q-value of the superallowed β-decay of 74Rb. Two beam times were performed to measure the mass of 74Rb and its daugther nucleus 74Kr. 74Rb is the shortest- lived nuclide ever investigated in a Penning trap (T1/2 =65ms).

The accuracy of its mass value is governed by statistics and resolving power that are limited by production − rate and half-life, respectively. The relative accuracy reached for the mass of 74Rb is about 3.4 ⋅ 10 7 (i.e. − ≈ 25 keV). The measurement of 74Kr was performed with an unprecedented relative accuracy of only 3 ⋅ 10 8. Additionally, the masses of the krypton isotopes with A = 73 and 75 were measured.

74 Experimental Physics Division One beam time was performed using a molten lead target to complete the picture of binding energies for the neutron-deficient mercury isotopes. The isotopes 179,180,181Hg were measured for the first time closing the gap in the binding energy sytematics.

The last beam time in 2000 was used to measure the mass of 34Ar produced in a CaO target. This value is needed with very high accuracy in the context of the FT-value systematics for superallowed fermi β-decays. ISOLTRAP succeeded in measuring this mass with an uncertainty below 1 keV.

Future mass measurements will be performed in astrophysically interesting regions like the neutron-rich Cd and Sn isotopes, the neutron-deficient Y isotopes, and around the rp-process waiting points 68Se and 72Kr. Additionally, the measurements in the context of fundamental tests will be continued measuring 32Ar. Future technical developments focus on the improvement of the overall efficiency by improving the detector set-up as well as different parts of the ion transfer.

IS304 / IS389

The laser spectroscopy study of nuclear structure in the sd shell was continued, and measurements of nuclear moments and isotope shifts of neon isotopes were essentially completed in 2000. The experimental method is an ultra-sensitive variant of collinear laser spectroscopy. Non-optical detection is based on optical pumping, state-selective collisional ionization and β-activity counting. This method enabled the investigation − of isotopes in the extended chain of 17 26,28Ne.

The small effect of nuclear radii on the optical isotope shifts of light elements requires very accurate measurements. The errors are dominated by uncertainties of the Doppler shifts as long as these are determined from measurements of the acceleration voltages. These uncertainties were removed by performing a direct beam energy measurement using the simultaneous excitation of two optical lines with the same laser in parallel/antiparallel beam configuration. This recently developed technique yields the energy of the 60 keV neon beam to less than 1 eV. Earlier preliminary isotope shift measurements were improved by the inclusion of this new calibration procedure. It turns out that nuclear structure effects in the radii are fairly well resolved.

In addition to the structure of lower sd-shell nuclei far from stability, the experiment yields key information on 17Ne at the proton drip line. This isotope is one of the most promising candidates for a proton- halo structure. A measurement of the charge radius is much more sensitive to proton halo effects and also more accurate than the existing data on matter radii. Another test for halo properties is offered by the nuclear magnetic moment which is extracted from the hyperfine structure. With the known magnetic moment of the mirror nucleus 17N one obtains the isoscalar moment. The result shows mirror symmetry in the appreciable contributions from the sd shell for the proton pair of 17Ne (presumably forming the halo) and the neutron pair of 17N.

IS323

Previous results obtained by our group in 1991 by means of track detectors gave a branching ratio for the − exotic 14C decay of 225Ac of the order of 10 12 [Bonetti et al., Nucl. Phys. A 562 (1993) 32]. Such a value, although rather small both in absolute value and relative to the well-known, and largely investigated, 14C

Experimental Physics Division 75 decay of 223Ra [M. Hussonnois et al., Phys. Rev. C 43 (1991) 2599], could nevertheless be at the limit of sensitivity of the large acceptance superconductive spectrometer SOLENO of IPN-Orsay, thus allowing one to perform a high-resolution study of the spectrum of 14C clusters. This motivated us to produce in June 1999 a 225 strong (Ra+Fr) source at ISOLDE by using the GP Separator and a dedicated thick ThC2 target. In five days’ irradiation time about 2 × 1015 225(Ra + Fr) atoms were produced, by taking advantage of the very high yield of radioactive atoms (up to 8 × 109 atoms/s) obtained with the new target. The 225Ac source obtained by β decay of Ra+Fr was subsequently transferred to Orsay, measured and inserted in SOLENO, whose magnetic field was optimized for transmitting 28.6 MeV, 5+ 14C ions.

The experiment turned out to be difficult because of the high flux of alpha particles which reached the detector placed in the focal point of the ion trajectories on account of (1) energy degradation due to multiple scattering or collisions with the residual gas atoms and (2) high intensity of the alpha source which resulted in considerable transmission of particles even in the tail of the transmission curve of the spectrometer. This caused not only a sudden damage of the ion-implanted silicon detector but also multiple pile-up events which unfortunately fall in the spectrum region in which 28–29 MeV 14C events were expected. The situation is shown in Fig. IS323–1. One clearly sees the intense peak of 8.375 MeV 213Po alpha particles, the degraded 4 MeV alpha particle bump, and their multiple pile-up peaks. The situation was unfortunately only partially alleviated by using a pile-up rejection circuitry. In the region of interest 10 events have been registered (Fig. IS323–1 shows one of these). However, the possible presence of pile-up events even in this high energy region does not allow one to unambiguously attribute them to 14C.

Fig. IS323–1

Because of the above problems, the 225Ac source was subsequently used for a new track detector experiment. A 2p assembly of glass track detectors was placed around the 1.35 mCi source. After 260 h irradiation time, glasses were etched in HBF4 and scanned under an optical microscope: 14 tracks have been found and unambigously attributed with the help of an accelerator calibration to 14C. The branching ratio − relatively to alpha decay comes out to be (4.5±1.4) 10 12, thus confirming the 1991 result of Bonetti et al. The results are being analysed.

76 Experimental Physics Division IS333

A chemically selective laser ion source has been applied in a decay study of very neutron-rich Cd isotopes at CERN/ISOLDE. Apart from its intrinsic importance to nuclear structure far from stability, the region around the doubly closed-shell nucleus 132Sn is also of astrophysical interest for the formation of the A~130 peak of the solar-system r-process abundance (Nr, ) distribution. Previous studies of decay properties of N=82 r-process nuclei, using non-selective plasma ion sources, were strongly complicated by isobar and molecular-ion contaminations. Only recently, progress in production and selection of Cd isotopes, in particular by applying chemically selective resonance-ionization laser ion-source (RILIS) systems at ISOLDE , allowed a continuation of our earlier work in the N~82 region.

130 ± For the classical ‘waiting-point’ nucleus Cd, we measure a T1/2 =(162 7) ms, which is more precise ± 131 ± than our earlier value of (195 35) ms. For the new N=83 isotope Cd, a T1/2 =(68 3) ms is obtained which is unanticipatedly short when compared to current model predictions for pure GT-decay

(e.g T1/2 = 943 ms from the QRPA model). Also the Pn ~ 3.5% is surprisingly low when considering the large β (Qβ–Sn)-window of about 5.8 MeV for dn-emission. A somewhat similar picture arises for the second 132 ± new isotope, N= 84 Cd. Its T1/2 =(97 10) ms is again considerably shorter than the predicted ± T1/2 (GT) = 633 ms. However, in this case, the large experimental Pn value of (60 15)% is at least in qualitative agreement with the predicted Pn (GT) = 100%.

IS349

In the past year new measurements were carried out, complementing the data set from previous runs. The β-asymmetry parameter was determined for the ∆J = 0 first-forbidden g.s. → g.s. β-transitions of 209Tl − (Ip = 1/2+), 209Pb (9/2+) and 213Bi (9/2 ). The nuclei were polarized using the low-temperature nuclear orientation (LTNO) method and β-asymmetries were measured with p-i-n Si diode particle detectors mounted inside the 4.2 K radiation shield of a 3He−4He dilution refrigerator and operating at a temperature of about 10 K. The activities were obtained in the α decay chains of the long-lived isotopes 223Ra and 225Ra. Foils with these two isotopes collected at ISOLDE were inserted into a He-gas-filled ion source at the LISOL isotope separator in Louvain-la-Neuve. In this ion source, the nuclei recoiling out of the foil after a decay were thermalized and ionized so that they could be mass separated and implanted into the cooled (millikelvin region) iron host foil in the dilution refrigerator of the LTNO set-up.

Large beta anisotropies were observed in all cases, approaching full saturation at temperatures of ≈10 mK for 209Tl and 213Bi. The analysis of these data is still in progress. Preliminary results yield an asymmetry parameter value of A = −0.36 (2) for the decay of 213Bi. From the asymmetry parameters, the ratios of the rank-zero to rank-one contributions in these ∆J = 0 first-forbidden beta transitions are obtained. Combining these with the ft-values then yields purely experimental values for the rank-zero contribution in these transitions as well as additional experimental information on the meson-exchange-induced renormalization of the weak axial-vector current. The meson-exchange-current-induced enhancement factors ε of the time-like γ component of the weak axial-vector current ( 5 matrix element), which can be extracted from the experimentally determined asymmetry parameters for each of the above-mentioned transitions, will be compared to the average enhancement factor ε≈2.0 (corresponding to a meson-exchange-induced enhancement of about 100% over the impulse approximation) which was deduced earlier from a comparison of ft-values and theoretically calculated matrix elements for transitions in the lead region [E.B. Warburton,

Experimental Physics Division 77 Phys. Rev. C44 (1991) 233]. The enhancement that is predicted by different theoretical models for meson exchange ranges from 40% to about 100%.

IS355

The project aims at studying the first forbidden unique (1u) radiative electron-capture decay of 81Kr × 5 (T1/2 =2.3 10 y) in low background conditions available in Warsaw. The intensity of the photon spectrum will be compared to predictions of the internal-bremsstrahlung theory. A question is whether an excess of the intensity will be observed, indicating the role of detour g/b transitions via intermediate virtual nuclear states, as detected already for the 1u radiative decay of 41Ca.

The part of the experiment performed at CERN was to fabricate a 81Kr source at ISOLDE by collecting the parent nucleus, 81Rb. Here, an amount exceeding 2 × 1016 atoms was needed because of the long half-life of the daughter nucleus. Collections were attempted in 1998 and 1999 but did not reach the final goal on account of technical problems and/or lack of beam intensity. However, after a very succesful collection in 2000, the desired amount of 81Kr-nuclei was attained. The samples, containing minute contaminations of activity from neighbouring masses, will now have to cool down for several years before the measurements can be commenced. However, with the successful collection of the needed activity, the CERN-specific part of the project is completed.

IS356

This project aims at a simultaneous measurement of the longitudinal polarization and the emission asymmetry (polarization–asymmetry correlation) of positrons emitted from polarized nuclei. Such an experiment is sensitive to the possible existence of several types of weak interaction that are not included in the standard electroweak model, such as e.g. right-handed (V+A) currents, scalar currents, and tensor currents. Its relative character (measurements are carried out with both polarized and unpolarized nuclei) eliminates or reduces significantly a large number of systematic errors. This method will allow an improvement of the existing limits for both right-handed currents and tensor currents in nuclear beta decay.

Data taking was started with 118Sb. The 118Sb nuclei were polarized with the method of low-temperature nuclear orientation. They were therefore implanted into an iron host foil that was subsequently cooled to millikelvin temperatures in a 3He–4He dilution refrigerator. Positrons were energy-selected with a spectrometer and then focused into a polarimeter where their longitudinal polarization was measured using the positronium hyperfine spectroscopy method. The analysis of the acquired data is still in progress. At the same time, the different sources of systematic errors are now being studied in detail, including both calibration measurements and simulations, in order to reduce systematic effects to the minimum.

IS358

The original proposal IS358 was based on exploration of the newly developed laser ion source to measure 68 the magnetic dipole moments of nuclear ground states in the vicinity of doubly magic 28 Ni 40 . We have already 67 67 β reported results of successful measurement of 28 Ni39 and Cu. Here we present results of -NMR

78 Experimental Physics Division measurement on 69Cu, 71Cu and the 68Cug leading to precise determination of ground state-magnetic moments of these nuclei.

69 Cu 68 67 29 40 - one proton above 28 Ni 40 is, like Ni, of strong theoretical interest. These nuclei are examples of pure single-particle configurations and, given this simplicity, their magnetic moments can be interpreted to throw light on subnucleon degrees of freedom in nuclei. A succesful measurement of the 69Cu magnetic µ 67 moment of 2.84 (1) N was made in 1999 (see Fig. IS358–1). This work together with results on Ni was recently published. 69Cu represents one of the rare cases of a nucleus with closed neutron shell and a single proton in the 1p3/2 shell.

Only two other cases of this configuration are within experimental reach; 11Li has a known magnetic moment and 57Cu has not been measured as yet. The unknown 57Cu magnetic moment cannot be obtained in a nuclear orientation experiment because of a too-long spin-lattice relaxation time as compared to its half-life of 0.23s. An experiment involving different techniques is planned in the near future to measure this important magnetic moment.

Apart from the fundamental information about subnucleon degrees of freedom (mesonic exchange currents and related corrections) obtained from magnetic moments of pure single-particle configurations, the changes in these configurations when moving away from closed shells are also of a considerable theoretical interest. Magnetic dipole moments are a particularly sensitive monitor of these changes. It is of particular value to follow the magnetic moment of a single nucleon state (proton in Cu isotopes), while the other nucleons, neutrons in this case, move between one closed shell (57Cu, N = 28) and the next (69Cu, N = 40). No such complete sequence of measured moments exists. It is expected that both the proton–neutron interaction and possible core excitations will make significant contributions to the structure of the single proton state, with the 1 pure shell model (1p3/2) as only one of many components of its wavefunction. Crossing to the next neutron shell (71Cu, N = 42) is also open to accurate theoretical calculation. The neutron-number dependence of odd- A Cu isotope moments known so far is shown in Fig. IS358–2 which includes the newly measured 67,69,71Cu. Two theoretical predictions for magnetic moments of 57,59Cu, based on shell model calculations, are included in the figure.

71 µ NMR/ON determination of the Cu moment of 2.28 (1) N was achieved in August 1999 (see µ Fig. IS358–3) after a rough value 2.3 (3) N had been obtained from a direct scan with the first step laser of the RILIS (experiment IS365) thus serving as a very useful guide in the search for the resonance signal in the βNMR/ON experiment. The 71Cu result indicates a considerable change in the neutron-number dependence of odd-A Cu magnetic moments (see Fig. IS358–3). The sharp change in slope observed in crossing the N = 40 neutron shell closure reflects changes in possible neutron configuration excitations. Detailed analysis of this result is in progress.

− Finally, NMR/ON measurement of the magnetic moment of 1 ground state of the odd–odd 68Cu (see µ Fig. IS358–4 was completed in August 2000. The magnetic moment of 2.39 (1) N, (assuming spin 1) for the 68Cug state was determined and its interpretation is in progress. This result agrees with the RILIS value 2.48 ± 0.02 ± 0.12 within errors and improves on its accuracy.

Experimental Physics Division 79 15

69 10 Cu

Destruction of asymmetry [%] 305 307 309 311 313 315 317 Frequency [MHz]

Fig. IS358–1: Beta-NMR/ON for 69Cu.

4.0 ] N

µ 3.6 expold expnew 3.2 Schmidt limit theory1 2.8 theory2

2.4 Magnetic moment [ 2.0 26 28 30 32 34 36 38 40 42 44 Neutron number

Fig. IS358–2: Magnetic moment of odd-A Cu isotope as a function of neutron number.

8 71Cu 6

Destruction of asymmetry [%] 240 245 250 255 260 Frequency [MHz]

Fig. IS358–3: Beta-NMR/ON for 71Cu.

80 Experimental Physics Division 2

68 g 4 Cu

Destruction of anisotropy [%] Destruction of anisotropy 6 387 389 391 393 395 397 399 401 Frequency [MHz]

Fig. IS358–4: Beta-NMR/ON for 68Cu.

IS361

Investigations of light nuclei close to the drip lines have revealed new and intriguing features of nuclear structure. The occurrence of halo structures in loosely bound systems has had a great impact on nuclear physics research in the last few years; as intriguing, but not yet solved, is the nature of transitions with very large beta strength.

We report here on the investigation of this latter feature by an accurate measurement of the beta-decay asymmetry between the mirror nuclei in the A = 9 mass chain. More specifically the aim of this experiment is to study asymmetries in beta decay rates of mirror nuclei. There are indications that the two mirror decays and are very relevant. An asymmetry has already been observed in the decays to the − + − 5/2 states at excitation energy ~2.4 MeV. The asymmetry parameter δ = (ft) /(ft) − 1 is determined to be 1.2 ± 0.5 (and possibly larger) which is one of the largest observed asymmetries of mirror states. The large uncertainty in the δ value mainly arises from incomplete knowledge of the 9C decay.

The 9C ions, produced by proton bombardment of a MgO-target at the ISOLDE facility at CERN, were stopped in a thin C-foil and the 9B* decay products were registered by two Double Sided Si Strip Detectors (DSSSDs) (5 × 5 cm2, 16 + 16 strips). To detect the high energy protons, the two DSSSDs (500 and 300 µm thick) were complemented by a 700 µm thick 2000 mm2 silicon detector and by a 1000 µm thick 5 × 5cm2 silicon PAD detector, respectively. The energies and angles of all fragments were thus measured in order to obtain the proton + alpha + alpha correlations. The sum of the three measured energies directly gave the excitation energy in 9B.

Summary of Obtained Results

A large β-strength asymmetry is deduced for the mirror transitions of 9C and 9Li to states around 12 MeV excitation energy. A satisfactory description of the three-body decay from this excitation level is obtained within a sequential model involving the ground a first excited states of 5Li and 8Be. From the study of angular − correlations the spin of the 12.2 MeV state is determined to 5/2 . A last experimental test of the large asymmetry found is to remeasure the 9Li decay with the same set-up. This will be done in the spring of 2001.

Experimental Physics Division 81 IS365

The IS365 Collaboration aims to obtain detailed nuclear spectroscopy information on isotopes close to the magic proton number Z = 28. Very neutron-rich and neutron-deficient copper isotopes are ionized with the ISOLDE resonance ionization laser ion source (RILIS) to provide beams with low cross-contamination. On the neutron-rich side, the spectroscopy with separated copper isotopes currently allows the closest approach to the doubly magic 78Ni at an ISOL facility. The problem for measuring the decay of very neutron-rich copper isotopes is the isobaric background. Going to masses around 78 and beyond, the background from neutron- deficient rubidium isotopes is dominating. This is due to the high production yields in high energy-fission induced by 1.4 GeV protons.

However, fission induced by low- or medium-energy particles (below some ten MeV) does not populate these nuclides. Such a ‘primary beam’ spectrum can be simulated at ISOLDE with a proton–neutron converter. The protons are no longer sent directly onto the target, but onto a heavy metal rod mounted in parallel to the target. Spallation neutrons (with some MeV energy) evaporated at large angles will hit the UCx/ graphite target and induce low-energy fission while the primary beam and the high-energy reaction products are strongly forward-peaked in a cone which does not hit the target. Using a Ta converter mounted at 24 mm (axis to axis) from the target (see Fig. IS365–1) we measured a ‘converter efficiency’ (i.e. the ratio of nuclide yields with beam onto the converter versus beam directly onto the target) of about 11% for very-neutron-rich isotopes in the far asymmetric wing of the fission product region (Cu and Ga).

The obtained beam purity allowed for the first time the study of the beta-gamma decay of 78Cu. Three + + + + gamma rays were identified: The 2 → 0 and the 4 → 2 transitions in the 78Zn daughter (730 keV and 890 keV respectively) and a 114 keV gamma ray in 77Zn populated by beta-delayed neutron emission.

UCx/graphite target D: 14 mm, l: 200 mm, 80 g 238 U in graphite cylinder, D: 20 mm

24 mm Ta rod, D: 10 mm, l: 215 mm, 280 g Fig. IS365–1: Geometry of the proton–neutron converter target.

IS373

The goal of the MISTRAL experiment [CERN-EP, CSNSM Orsay, IAP Bucharest, GSI Darmstadt Collaboration, originally approved as IS346 (now completed) and continuing as IS373] is to perform precision measurements of the masses of exotic nuclides produced at CERN’s mass separator facility ISOLDE. MISTRAL is especially suited for this vocation due to its very rapid measurement time that gives access to the shortest-lived (i.e., most exotic) nuclides that can be produced.

The ISOLDE beam is injected into the spectrometer which is composed of a homogeneous magnetic field of 1 m diameter and makes two turns (at the cyclotron frequency) before being directed onto a detector. At the beginning and the end of one cyclotron period the beam energy is modulated by a longitudinal, radiofrequency electric field. When the scanned radiofrequency corresponds to an integer-plus-one-half multiple of the ion

82 Experimental Physics Division cyclotron frequency, the recorded signal will exhibit a high-resolution peak, the position of which is compared to that of a calibrant mass to obtain a high-precision measurement.

The data collected during the 1999 run with the plasma ion source have now been analysed and were the subject of the Collaboration’s second doctoral thesis. Difficulties with the enormous amount of (sometimes unidentifiable) isobaric contamination limited the success of this run to only three new measurements: − 25 26Ne and the exotic nuclide 32Mg, an important candidate for the phenomenon of shell ‘openings’ that happen in nuclear configurations of extreme neutron-to-proton-number ratio. The magic number at N = 20 should normally be a shell ‘closure’.

An attempt was made in early 2000 to improve these measurements using isobaric mass doublets directly − from the ISOLDE beam but only with limited success (29 30Mg) due to insufficient production and omnipresent contamination.

The balance of allotted shifts for commissioning the spectrometer are scheduled for 2001 when we shall exploit the beam purity afforded by the laser ion source to confirm and extend the measurements to heavier Mg isotopes. In the meantime, a measurement was made late in 2000 of the N = Z nuclide 74Rb, a superallowed β-emitter of interest for constraining the electroweak sector of the Standard Model (see IS384).

32 T = 95 ms 8 Mg ½ 400 TOFI86 6 4 (keV) 300 SPEG87 TOFI91 counts a 2 200 SPEG91 0 24022 3 2402 25 24022 7 freque ncy (kHz) AME95 100 -

AME95 0

AME+ -100 MIST RAL

-200 TOFI91 b MISTR AL99 MISTRAL99 -300

Fig. IS373–1: MISTRAL measurement of 32Mg with respect to other values comprising the mass in the evaluation (Audi & Wapstra, 1995). The overbinding of this exotic, normally closed-shell nuclide enhances the shell ‘opening’ effect due to nuclear deformation. (inset) The recorded, high-resolution mass peak.

IS376

− The purpose of the experiment is to initiate studies of very-neutron-rich neon isotopes, 28 32Ne, using the ISOLDE HRS. In this region there is a possibility to encounter p-wave halo states. So far 29Ne has been reached and the data indicate an improved Pn-value for 29Ne as well as an improved P2n-value for this isotope, data that will be published presently.

For 8He, low-enery neutron spectra with extremely good statistics have been obtained. The data is under − analysis. The remaining shifts will be dedicated to searching for 30 32Ne.

Experimental Physics Division 83 IS377

The IS377 experiment aims to investigate the Gamow–Teller strength, isospin symmetry, and proton– neutron interaction in the region a nuclide chart where large deformations occur. These studies need detailed information on the low-energy levels in the nuclei. Ground-state masses of Sr and Y nuclei will be studied by using the Penning trap mass spectrometer ISOLTRAP and the low-energy levels of 75Rb and 78Y by β-decay spectroscopy. The information obtained can also be used to extend the experimental database for astrophysical rapid proton capture modelling. During 2000 the first step was taken by measuring the masses of 76,77Sr. The improvement in the absolute mass value of 76Sr will lead to a significant gain in accuracy of the Gamow– Teller strength involved in the decay. The large deformation of this nucleus has been predicted to alter the strength distribution and this different pattern could possibly be used as a signature of a certain deformation. In addition, 76Sr, with its long β-decay half-life of 9 s, might act as a waiting-point along the rp process path and the absolute mass is crucial for determining the proton capture rate of this nucleus. The IS377 experiment will continue data-taking during 2001 with mass measurements of Y isotopes and with decay spectroscopy on 75Sr and 78Y.

IS381

Isospin mixing in N ≈ Z nuclei is an important phenomenon in nuclear physics, which has recently gained both theoretical and experimental interest. It also forms an important nuclear physics correction in the precise + + determination of the ft-values of T = 1 superallowed 0 → 0 β transitions. The latter are used in precise tests of the weak interaction in nuclear beta decay, i.e. for the determination of the Vud element of the Cabibbo– Kobayashi–Maskawa quark-mixing matrix, which is important in testing unitarity. The IS381 experiment investigates isospin mixing into nuclear ground states in the N ≈ Z region, by determining the isospin – π π forbidden Fermi-component in the Gamow–Teller-dominated J → J β transitions through the observation of anisotropic positron emission from oriented nuclei.

First data were obtained in the decay of 71As. The activity was collected at ISOLDE in a Fe foil and subsequently transported to Leuven where it was inserted into a 3He−4He dilution refrigerator. The nuclei 71As were cooled to the millikelvin region and subsequently polarized using the low-temperature nuclear orientation (LTNO) method. β-asymmetries were measured with HP Ge particle detectors mounted inside the 4.2 K radiation shield of the refrigerator and operating at a temperature of about 10 K. The temperature was determined from the anisotropy of a calibrated 57CoFe nuclear orientation thermometer. Large beta anisotropies were observed for the polarized 71As nuclei. The analysis of these data is still in progress.

IS382

The origin of the rare, neutron-rich isotope 36S remains a debated question. One of the key reactions in the s-process nucleosynthesis network leading to 36S is 39Ar(n,α)36S. This reaction has never been studied so far, 39 which is due to the fact that Ar is a radioactive (T1/2 = 269 y) gas, which is not commercially available.

During a three-day experimental campaign, a suitable 39Ar sample was prepared at ISOLDE. A dedicated titaniumoxide target (8 g/cm2) was bombarded with 1 GeV protons from the PS Booster. In order to obtain a pure argon beam, a water-cooled transfer line was used to freeze out less volatile isobars before they can reach

84 Experimental Physics Division the ion source. Adding stable argon with a calibrated leak to the ion source allowed the determination of the ionization efficiency (3.5%). For the isotope separation, the low-mass side (GLM) of the General Purpose + Separator was used. After magnetic separation, 39Ar ions (1 ) were implanted at 60 keV in a 12 µm thick aluminium foil. The yield was about 5 × 108 39Ar ions per µC.

The number of atoms was derived from a measurement of the 0.6 MeV β’s emitted during the decay of 39Ar using a 4π pressurized proportional counter. This yielded a number of 3 × 1014 39Ar atoms on the sample.

With this sample, a first experiment has been performed at a thermal neutron beam of the high flux reactor of the Institut Laue-Langevin in Grenoble (F). From this measurement an upper-limit of 0.26 b could already 39 α 36 be determined for the Ar(nth, ) S reaction cross section, which is one order of magnitude lower than the theoretical estimation.

IS383

The aim of the IS383 programme is to perform laser spectroscopy measurements in the neutron-rich tin isotopes in order to investigate nuclear properties as charge radii and electromagnetic moments of the ground and isomeric states.

The tin isotopic series has a proton closed shell (Z = 50) and includes a neutron-rich doubly-magic isotope: 132 50 Sn 82 . Thus a very stringent test of the effective nuclear forces far from stability can be obtained through the theory–experiment comparison of global properties like the mean square charge radius change in tin isotopes.

The Sn isotopes are obtained at ISOLDE by bombarding an UCx target with the 1 GeV PS Booster proton beam. This target is associated to a hot plasma ion source or to a laser ion source. But in both cases, the ion beam delivered by ISOLDE is not a pure Sn beam. In particular, the yields of Cs can be very perturbing for the laser spectroscopy measurements. Thus this experiment on Sn neutron-rich isotopes is a challenge for both experimental set-up COLLAPS (collinear laser spectroscopy) or COMPLIS (resonant laser ionization on desorbed atoms). Therefore tests were needed to define the best experimental conditions.

The first tests performed with the COMPLIS experimental set-up are quite promising. From the 2 23 → 2 3 126−132 5s 5p P0 5s 5p6s P1 optical transition at 286.3 nm, the isotope shift of the even-even Sn nuclei have been measured for the first time. The frequency resolution obtained is sufficiently high to allow the evaluation of the change in the mean square charge radius.

− A 10 5 efficiency was obtained, which means the measurements can be extended to 134Sn. The next experiment with COMPLIS will be dedicated to the 134Sn study and to the hyperfine structure measurements − − of the odd 127 133Sn isotopes and of the 125m, 127m 131mSn isomers. Tests with COLLAPS are also planned to measure the spin values of some isomeric states.

Experimental Physics Division 85 IS384

Superallowed β decays can be used to test the conserved vector current (CVC) hypothesis. Provided the

CVC is valid, the obtained value for the vector coupling constant GF, together with muon decay data, can be used to extract the up-down quark mixing matrix element Vud of the CKM matrix. This makes possible an unitary test of the matrix and thus it serves as a test for the Standard Model. Theoretical corrections including charge-dependent corrections are the largest source of uncertainty in the data collected for the superallowed Fermi decay systematics.

The IS384 experiment aims to reduce these uncertainties by measuring high-precision data on β-decay Q- value, half-life, and decay branching ratios of a Fermi β emitter 74Rb. In this mass region the charge- dependent effects are expected to be large and identifiable in the decay as non-analog transitions. Several measurements were performed during 2000 including mass measurements of the mother 74Rb and the daughter 74Kr with ISOLTRAP and MISTRAL mass spectrometers and searches for non-analog transitions by β-delayed γ and conversion electron measurements. In the conversion electron measurement a non-analog + transition to the low-energy 0 state in the daughter nucleus 74Kr was observed in the work and it allows for an estimate of the Coulomb mixing correction. The data is partially under analysis and will be published during the year 2001.

IS387

The neutron-rich Tl, Pb and Bi isotopes are of exceptional interest in order to trace the evolution of single- particle levels away from the doubly magic 208Pb towards the neutron-rich side of the nuclear chart. While 208Pb is well understood in terms of the shell model, experimental data on the heavier isotopes is very scarce and it is far from clear to what extent the shell model is upheld. Furthermore, large branching ratios for beta- delayed neutron emission are expected in this mass region, adding astrophysical interest to the subject.

Beta-decay studies at online mass separators, however, often suffer from mass contaminations. The pulsed-release technique, succesfully pioneered at ISOLDE, allows one to considerably reduce the contamination whenever the isotopes of interest are longer lived than the unwanted species. In the mass region 215

In a test run for IS387 late last year we complemented the pulsed-release suppression of contaminants with the element selectivity of the ISOLDE laser ion source. Comparison of the spectra recorded by a beta-X and beta-gamma coincidence set-up with and without laser irradiation of the ion source allowed us to unambiguously identify the gamma de-excitation pattern following the beta decay of 215Pb. Analysis of the data, moreover, shows that the gamma cascade seen in the earlier data originated from 215mBi rather than 215Pb. The deduced production rate for 215Pb, determined at 1 at/µC, is several orders of magnitude lower than expected from the extrapolation of abrasion-ablation calculations.

In the experimental campaign of next year, the measurements will be extended to heavier Pb isotopes as well as neutron-rich Tl and Bi.

86 Experimental Physics Division Solid-State Physics

IS307

By means of radiotracer experiments the diffusion of Au and Pt in radiofrequency-sputtered amorphous silicon (a-Si) was investigated. Specimens of a-Si with homogeneous doping concentrations of Au or Pt in the range 0–1.7 at.% were produced by co-sputtering of Si and Au or Pt, respectively. An additional tiny concentration of radioactive 195Au or 188Pt, about 10 at.ppm, was implanted at ISOLDE. The resulting Gaussian distribution of the implanted atoms served as a probe for measuring diffusion coefficients at various doping concentrations. It was found that for a given doping concentration the diffusion coefficients show Arrhenius-type temperature dependencies, where the diffusion enthalpy and the pre-exponential factor depend on the doping concentration.

From these results it was concluded that, in a-Si, Au and Pt undergo direct, interstitial-like diffusion that is retarded by temporary trapping of the radiotracer atoms at vacancy-type defects with different binding enthalpies. In the case of Au in a-Si, the influence of thermal-annealing-induced structural relaxation on the diffusivity has been investigated. It was found that the diffusion coefficients pass through a maximum during relaxation. We propose that this behaviour arises from an agglomeration of vacancies which results in trap deepening.

To check this idea, further experiments were done in which some specimens with different doping concentrations were exposed to particle irradiation during diffusion annealing. These specimens were + implanted with 195Au at ISOLDE and subsequently diffusion-annealed under 1 MeV-N irradiation at the pelletron-type linear accelerator of the Max-Planck-Institut für Metallforschung in Stuttgart, Germany. It was found that high implantation doses in combination with great diffusion lengths give rise to complicated shapes of the diffusion profiles. These were shown to be due to diffusion retardation on the vacancy-rich side and diffusion enhancement combined with localized diffusion retardation on the self-interstitial-rich side of the 195Au implantation peak.

IS318

The IS318 Collaboration predominantly studies ultrathin metallic multilayers and isolated atoms at surfaces and interfaces. With the aid of radioactive ions we get information on structural and electronic properties. For this project the UHV-chamber ASPIC (Apparatus for Surface Physics and Interfaces at CERN) is installed at the UHV-beamline of the Booster-ISOLDE facility. Recent experimental results are described below.

Increasing electric field gradients (EFG) with increasing temperature were observed at isolated Se adatoms on Ni(111), Pd(111), and Co(0001) surfaces applying PAC (perturbed angular correlation) spectroscopy. This finding is in contrast to EFGs at probes on surfaces with (001) orientation and in metallic bulk systems. We correlate the results with the EFG dependence on the adatom distance from the surface, as calculated by the discrete variational molecular/cluster method (B. Lindgren/Uppsala). The sign changes from negative EFGs on (001), to positive EFGs on (111) surfaces. We conclude that on surfaces with (001) orientation the isolated adatom impurity is closer to the substrate in comparison to surfaces with (111) orientation. Such a behaviour

Experimental Physics Division 87 was not observed for monolayer coverage of Se in earlier photoelectron diffraction measurements [D. H. Rosenblatt et al., Phys. Rev. B 26 (1982) 3181].

Radioactive cadmium isotopes were positioned on the (111) and (001) surface of ferromagnetic nickel at different sites such as edges, kinks, terraces, etc. A whole set of magnetic hyperfine fields Bhf was measured at these sites using the PAC, Fig. IS318–1. The magnetic fields strongly depend on the local environment of the cadmium impurities and can be correlated to the respective coordination numbers. Applying the information obtained in calculations the field is believed to become positive for lower coordination numbers. 111 − 111 There is a striking difference seen in the fields at Cd in Ni bulk, Bhf = 7 T, and Cd as adatom on + Ni(111), Bhf = ( )16 T. The values of the magnetic hyperfine fields may be interpreted on the basis of electronic properties of the sp-elements which have been calculated earlier.

Fig. IS318–1: Magnetic hyperfine fields at 111Cd on Ni versus coordination number. Nos. 4 and 6 for Ni(001) are taken from J. Voigt, PhD thesis, Konstanz, 1990, unpublished.

IS342

Project No.1: Lattice location studies of rare earth elements implanted into diamond

The lattice locations of rare earth isotopes 141Pr, 149Eu and 169Tm have been studied using the emission channelling technique. After implantation of corresponding precursors of mass 141, 149 and 169 at doses of − − − 1 × 1013 cm 2, 4 × 1013 cm 2 and 2 × 1013 cm 2, the diamonds were annealed in vacuum at 900°C for ten minutes. To study the lattice location, two-dimensional raster scans were performed on the conversion electrons arising from the 141Ce−141Pr, 149Gd−149Eu and 169Yb−169Tm decays and were compared with theoretical simulations based on the manybeam formalism.

Project No. 2: Lattice location and Mössbauer studies of rare earth elements implanted into 6H-SiC

The lattice locations of rare earth isotopes 149Eu and 169Tm were studied by means of the isotopes’ conversion electrons using the emission channelling technique. Precursors of these ions were implanted at − − doses of 4 × 1013 cm 2 and 2 × 1013 cm 2 respectively. In the case of 149Eu, lattice location and annealing studies were performed after annealing in vacuum for 10 minutes from room temperature to 1000°C in steps

88 Experimental Physics Division of 150°C. In the case of 169Tm, similar studies were performed in the annealing temperature range from room temperature to 800°C. Finally, first Mössbauer studies were performed on the annealed 149Eu sample on the 149 149 decay Eu to Sm at room temperature using a Sm2O3 absorber.

Project No. 3: Temperature-dependent lattice location and diffusion studies of 8Li in 3C, 4H and 6H-SiC

8Li was implanted into three SiC polytypes and the intensities of the alpha particles arising in the decay were recorded online using a two-dimensional, energy-sensitive detector. The implantation temperature was varied between 100 K and 900 K. The obtained spectra were compared with Monte Carlo simulations in order to study lattice location and diffusion behaviour of lithium in the different SiC polytypes.

IS345

The IS345 Collaboration (Konstanz, Berlin, Bonn, Duisburg, Erlangen, Freiburg, Jena, Lisbon, Caen, Paris, Troitzk, CERN) studies the hydrogen diffusion and hydrogen passivation mechanism in binary and ternary III-V semiconductors. For this purpose nuclear methods like γ−γ perturbed angular correlation (PAC) are combined with electrical and optical techniques like Hall effect measurements or photoluminescence spectroscopy. The behaviour of hydrogen in III-V semiconductors has been studied in great detail in recent years, largely focused on the modification of the electronic properties due to the interaction of hydrogen with electrically active centres. The formation probability, the atomic structure, and the thermal stability of complexes formed between dopants and hydrogen have been extensively studied both theoretically and experimentally and experiments at ISOLDE have contributed to the clarification of the structure of the formed complexes and the determination of their thermal stability.

Knowledge of the fundamental mechanisms of hydrogen diffusion in III-V semiconductors is much less advanced. Most of the experimental results available up to now are based on macroscopic techniques like the determination of diffusion profiles of deuterated samples by SIMS or the observation of carrier profiles obtained in hydrogenated samples, where the sample is part of a Schottky diode which allows the annealing with a reverse bias applied across the Schottky contact. The interpretation of the data obtained by these + − techniques is influenced by the different charge states of hydrogen in semiconductors (H , H0, H ). Moreover, the charged hydrogen species interact with dopants present in the sample, resulting in experimentally determined diffusion properties which are governed by the trapping and detrapping of the hydrogen rather than by the fundamental properties of the diffusing hydrogen. One essential part of the IS345 experiment is the direct observation of the jump of free hydrogen away from a lattice atom located next to it. Using the radioactive acceptor 117Cd, Cd-H pairs are formed in III-V semiconductors. After the decay of 117Cd to 117In, H is no longer bound to an acceptor and can diffuse freely. This diffusion can be observed locally by PAC as function of temperature. Results for the intrinsic hydrogen diffusion have been obtained for InP, InAs, and GaAs.

Another set of experiments is focused on GaN which is used as material for LEDs and laser diodes in the blue and UV region. Using the radioactive acceptor 117Cd, Cd-H pairs should be formed in this III-V semiconductor. After the decay of 117Cd to 117In, H is no longer bound to an acceptor and can diffuse freely. A prerequisite to these studies is the annealing of the implantation damage. After implantation of 117Cd, the lattice is damaged and the concentration of intrinsic defects is higher than the dopant concentration. So, H would be trapped by lattice defects. It is known from former experiments with 111mCd, that the annealing of

Experimental Physics Division 89 GaN is difficult because the material degrades at the required high temperatures. We have used a new technique and annealed the samples under Al overpressure. Afterwards, they have been loaded with hydrogen. The measurement at 10 K revealed the existence of H in the nearest neighbourhood of a part of the 117In probes. Even using these enhanced annealing procedures, the small fraction of probe atoms observing hydrogen indicates that only about 5% to 10% of the implanted 117Cd acceptors can be electrically activated during the annealing treatment. This also has been confirmed by the direct determination of the optical and electrical activation of Ag and Cd dopants in GaN using photoluminescence spectroscopy and Hall-effect measurements. Using 111Ag/111Cd as ‘tracer’ for these techniques, the optical transitions and the electrical carriers associated with the doping has been unambiguously identified.

IS357

The project is aimed at the identification and characterization of gold and platinum impurities in crystalline silicon. It includes studies of homo- or hetero-nuclear pairs as well as their complexes with other common impurities like iron and lithium. The combination of powerful spectroscopic techniques such as photoluminescence (PL), deep level transient spectroscopy (DLTS) and magnetic resonance (EPR) is proposed and designed to provide new information not obtainable by any other techniques. The decay of radioactive isotopes through a decay chain will provide great finesse in the study of particular defect families.

Our results to date have enabled us to make unequivocal statements about the involvement, or not, of Au and Pt in a variety of defects studied.

From photoluminescence measurements:

– A spectrum (777 meV line) previously assigned to silver is due to Pt–Fe

– Another spectrum (735 meV line) assigned to iron is due to Au–Fe

– A third assigned to iron-boron pairs (1066 meV line) is also gold-related

– A fourth assigned to platinum (811 meV line) is not platinum related

– A new spectrum (785 meV) due to Hg has been observed

From DLTS measurements:

– Two new Au acceptor levels have been observed in n-type Si

– Three Pt levels have been identified

– The Au–Fe level has been observed

– Ir- and Os-related levels have also been observed

EPR measurements:

The first successful results for EPR measurements using radioactive isotopes were obtained in 2000. The measurements were performed on silicon implanted with 195Hg atoms, which transform into 195Au. These decay with half-life of 183 days to form the stable 195Pt isotope.

90 Experimental Physics Division In the experiments only the two well-known centres, the AuFe and PtFe impurity pairs, were identified. A change of EPR intensities ratio with time has been observed in accordance with the nuclear decay (Fig. IS357–1). Precise measurements of the hyperfine interaction constant A show a slight difference between the 195AuFe and 197AuFe centres. This is understood on basis of the Bohr–Weisskopf effect. In future experiments, the complexing of Au and Pt with Li and H will form the main focus of the work.

1.0

0.8

0.6

0.4 AuFe EPR intensity

195 0.2 PtFe/

195 0.0

0 50 100 150 200 250 300 350 Time (days)

Fig. IS357–1: Ratio of the intensities of the Pt–Fe and Au–Fe EPR centres as the Au–Pt transformations proceeded.

IS359

+ The experiments concentrated on high-temperature implantations, 400–800 K, of 57Mn ions

(T1/2 = 1.5 min) into silicon, Si1−xGex, and Si1−xSnx single cystals and measurements of Mössbauer spectra for the 14 keV γ-rays emitted in the decay of the 57Fe daughter nuclei. Basically three lines are seen in the spectra, which are assigned to be due to substitutional Fes and interstitial Fei in two different configurations. The fraction of substitutional Fes is constant up to at least 750 K. Its occurrence is attributed to an annealing reaction of interstitial Mn with the lattice vacancies created in the implantation process. This leads to a substitutional location for the majority of the implanted 57Mn atoms and this location is not altered in the subsequent decay to 57Fe for a certain fraction of atoms. However, an avarage recoil energy of 40 eV imparted − on the 57Fe daughter atoms in the β -decay leads also to the displacement of a sizeable fraction into tetrahedral interstitial sites. At ≤ 500 K this fraction is immobile within the lifetime of the Mössbauer state (140 ns). The Fe electron density on interstitial sites, as determined from the measured isomer shift, depends on the Fermi-level in differently doped silicon, whereas that on substitutional sites is constant. This is in +/0 accordance with, respectively, a well-known deep donor level for interstitial Fei, resulting in Fei charge states, and with theoretical predictions of no band gap states for substitutional Fe. The measured isomer shift values are consistent with calculated values for both lattice sites and charge states. The Mössbauer line from ≈ interstitial Fei shows diffusional line broadening at 600 K, i.e. a few diffusional jumps occur within the lifetime of the Mössbauer state. The line dissapears from the spectra at higher tempertures. The onset of the line broadening depends on the Fermi level; the data are currently being anaysed to deduce a predicted charge-

Experimental Physics Division 91 state dependence of the Fei diffusivity. Gradually, with increasing temperature, a new line occurs in the ≈ spectra, which is attributed to a unexpectedly stable configuration of interstitial Fei. It is stable up to 800 K. The preliminary analysis of the data indicate that this configuration could be a metastable complex formed with the vacancy, which is created in the recoil process. The nature of this complex is to be investigated further.

IS360

The aim of the IS360 Collaboration is to study High Temperature Superconductors (HTSc) by combining conventional characterization techniques with local characterization nuclear techniques, which are currently being used by solid-state-physics researchers at ISOLDE.

In 2000 a first addendum to the IS360 proposal (CERN/INTC 2000–039, INTC/P86 Add. 1) was presented and approved by the INTC Scientific Committee. The phenomena we are investigating concern the measurements of local charge asymmetries, which we have shown to occur at low temperatures in the Hg based HTSc compounds. The possible correlation of such phenomena with the existence of ‘stripes’ is being investigated. ‘Stripes’ are currently thought to be due to the segregation of holes away from regions of local moments, which lead to alternating regions at the nanometer scale with different structural and electronic properties. So far it is not known under which conditions such phenomena occur within the materials or whether they are intrinsically related with high-Tc superconductivity, either inhibiting or enhancing it.

Further experiments will start during 2001, to investigate atomic engineered nanostructres, consisting of − BiSrCaCuO/SrCaCuO intergrowth. These materials show room-temperature resistivity below 10 9 Ω.cm and non-linear I (V) current relationship that suggest a superconductor behaviour. So far, susceptibility measurements have not been able to show relevant diamagnetic properties due to the interference of the substrate signal. By using nuclear techniques, we intend to study the material’s hyperfine fields that could reveal the presence of magnetic fields, to be studied as a function of temperature.

IS362

IS362 performs a systematic diffusion study in GaAs, GaP, and GaN using suitable radioactive probe atoms that are available at the ISOLDE facility of CERN. Upon implantation of appropriate samples, diffusion annealing is carried out at our laboratory in Münster. For diffusion profile measurements we use ion-beam sputtering in conjunction with radioactivity counting techniques.

In the course of 2000 we processed the bulk GaAs wafers that were implanted with mass 73 in October 1999. Most samples selected for this shift were electronically extrinsic, i.e. either p-type due to Zn doping or n-type due to Te-doping. The implanted isotope decays within a few hours to the radiotracer 73As (half-life 80.3 d) which is well suited for diffusion studies. Earlier experience revealed that evaporation during diffusion annealing even in As-rich ambient leads to non-erosive loss of tracer as well as to erosive loss of sample material. In the present experiments these effects were considerably reduced by the use of silicon nitride capping layers which were grown on the implanted samples by chemical vapour deposition at the University of Bonn. However, this capping technique becomes ineffective at temperatures higher than about 1000°C. On the other hand, at temperatures below about 900°C self-diffusion on the As sublattice in GaAs becomes so

92 Experimental Physics Division slow that it does not lead to a measurable broadening of the implanted isotope layer within tractable annealing times, i.e., within several weeks.

The 73As diffusion coefficients obtained from the new GaAs samples confirm the preliminary picture emerging from the earlier experiments. The effects of doping on 73As diffusion turn out to be rather weak: a small enhancement for the strongly Zn-doped samples goes along with a yet smaller retardation for the moderately Te-doped samples. This provides evidence for the view that self-diffusion on the As sublattice in GaAs is dominated by an electrically neutral native defect under intrinsic conditions, although the minor contribution of a positively charged may not be totally neglected. Combining this finding with other recent results points to the neutral As interstitial as most important diffusion vehicle on the As sublattice in GaAs.

During the October 1999 shift we also implanted GaP crystals with mass 75 which decays in roughly one day to the long-lived isotope 75Se (half-life 118.5 d). Also these crystals were provided with a silicon nitride capping layer in order to reduce evaporation loss. From the currently performed 75Se diffusion experiments we hope to gain information about the native point defects that control diffusion on the P-sublattice in GaP.

104 as implanted

103

2 10 after diffusion 889 ˚C, 26 d

101

100 As concentration / arbitrary units arbitrary / concentration As

73 simulation

10-1 0 250 500 750 depth / nm

Fig. IS362–1: Diffusion-induced broadening of an implanted 73As distribution in GaAs.

IS369

The IS 369 experiment, a collaboration between the Universität des Saarlandes, the Universität Konstanz, and the ISOLDE group, uses radioactive probes delivered by the ISOLDE facility for the investigation of II-VI semiconductors. The radioactive isotopes are employed as dopant atoms in order to help to optimize the electrical and optical properties of II-VI semiconductors. In 2000 within the IS 369 experiment, the isotopes 77Br, 111Ag, and 117Cd were used for perturbed γγ-angular correlation (PAC) investigations, the isotope 111Ag in addition for diffusion experiments in CdTe, and the isotope 71As for photoluminescence (PL) investigations. These isotopes have been delivered during two beam periods.

Experimental Physics Division 93 In the beam period in May 2000, a ZrO hot plasma source was used for extracting and implanting 77Br into CdTe, ZnTe, and ZnSe, and 71As into CdTe and ZnSe. The isotope 77Br was used for PAC and the isotope 71As for PL investigations. In II-VI semiconductors, the parent 77Br represents a donor in the group VI sublattice and decays to 77Se, which is isoelectronic or identical to the respective group VI host atom. The PAC investigations upon the interaction of the group I acceptors Cu, Ag, and Au with the donor probe 77Br/ 77Se were started in CdTe in 1999 and were extended to the compounds ZnSe and ZnTe in 2000. The doping with the group I acceptors was performed both before and after implantation of 77Br. The iostope 71As was implanted into CdTe and ZnSe and represents an acceptor on the group VI sublattice in these materials. The PL investigations confirmed the incorporation of 71As as an acceptor by the decreasing intensity of the respective PL signal. There was no impurity level detected for the daughter 71Ge. Surprisingly, after the second decay to 71Ga an acceptor level was observed again, although Ga is normally incorporated as a donor in II-VI semiconductors. Moreover, this acceptor level is shallower than all known acceptors in the respective II-VI compound.

In August 2000, the UC2 target operated with laser extraction (LIS) supplied 111Ag, which was implanted into CdTe and used for PAC investigations. Here, the interaction of Ag acceptors with interstitial Ag donors was the centre of interest. The very high mobility of Ag in CdTe, which was indicated during the experiments in 1999, was investigated by dedicated diffusion experiments. At low Ag concentrations, after diffusion at 550 K an extended depletion zone of up to 100 µm from the surface was observed, although no out-diffusion of Ag could be detected. After subsequent diffusion of Cu into the CdTe crystal (550 K) from the side of implantation, the 111Ag atoms were observed to migrate to the back of the crystal completely. From the same target, 117Ag, decaying within few minutes to the PAC probe 117Cd/117In, was delivered and implanted into CdTe. The first, exploratory experiments with this PAC probe were addressed to the potential compensation of In donors by the formation of so-called DX-centres.

In all, the availability of suited radioactive isotopes has turned out to contribute to an improved understanding of the behaviour of dopant atoms, in particular of acceptor dopants, in II-VI semiconductors. The availability of numerous radioactive isotopes, suitable for PAC and PL investigations, is an important prerequisite for flexible and successful investigations towards an optimization of II-VI semiconductors.

IS372

The amorphous ceramic a-Si28C36N36, which is produced from a polymeric precursor by pyrolysis at 1050°C, consists of two amorphous phases, a-Si3N4 and a-C, whose volume fractions and domain sizes are approximately equal. The only structural change during a subsequent thermal 2-h anneal at 1200°C or 1350°C is an increase of the domain sizes from about 0.6 nm in the as-produced state (state 1) to about 1.4 nm (state 2) or 2.2 nm (state 3), respectively. The chemical reactions and structural changes induced by heat treatments above 1450°C, leading from the amorphous transistory state to the final crystalline ceramic, are diffusion- controlled. Therefore, the understanding of self-diffusion in a-Si28C36N36 and in its phases as well as the knowledge of the corresponding diffusion coefficients are of both scientific and technological importance.

Since the most reliable method for measuring diffusivities in solids is the radiotracer technique and since 11 the only suitable radioisotopes of carbon and nitrogen are the very short-lived C(t1/2 = 20.38 min) and 13 N(t1/2 = 9.96 min), a new facility has been constructed, which enables us to perform in situ measurements quasi-on-line at ISOLDE. The implantation of the radiotracers at ISOLDE is followed immediately by in situ

94 Experimental Physics Division diffusion annealing. The diffusion coefficients can be extracted from the diffusion broadening of the + implantation profiles, which, also in situ, are determined by serial sectioning using Ar -beam sputtering. First 11 results have been obtained for the diffusion of C in state 1 and state 3 of a-Si28C36N36 as well as in its phases a-Si3N4 and a-C. Further measurements are planned which aim at systematic investigations of the temperature dependences of the diffusivities of carbon and nitrogen in a-Si28C36N36, a-Si3N4, a-C, and Si–B–C–N- based ceramics.

IS380

It is generally accepted that Ge and Si differ considerably with respect to intrinsic-point-defect-mediated diffusion. In Ge, the native point defects dominating under thermal-equilibrium conditions at all solid-state temperatures accessible in diffusion experiments are vacancies, and therefore Ge self-diffusion is vacancy- controlled. In Si, by contrast, self-interstitials and vacancies coexist in thermal equilibrium. Whereas in the most thoroughly investigated temperature regime above about 1000°C Si self-diffusion is self-interstitial- controlled, it is vacancy-controlled at lower temperatures.

According to the scenario displayed above, self-diffusion in Si–Ge alloys is expected to change from an interstitial mechanism on the Si side to a vacancy mechanism on the Ge side. Therefore, 71Ge self-diffusion experiments in Si1−yGey as a function of composition y are highly interesting.

In a first series of experiments the diffusion of Ge in 0.4 to 10 µm thick, relaxed, low-dislocation-density monocrystalline Si1−yGey layers epitaxially grown on Si substrates was measured for the compositions y = 0.05, 0.10, and 0.25. The measurements were done by means of a radiotracer technique, in which 71Ge ions with the convenient half-life of 11.2 d were implanted with an energy of 60 keV to depths of about 30 nm and in which serial sectioning of the specimens was performed by ion-beam sputtering.

The diffusion studies just described yield diffusion coefficients D as functions of the diffusion temperature − T. Irrespective of the Ge content, the diffusivities obey Arrhenius’s laws, D = D0 exp( H/kT), whose activation enthalpies H and pre-exponential factors D0 are compiled in the subsequent table, which, for comparison, also contains data on bulk Si0.05Ge0.95 as well as data from the literature on pure Si and Ge.

y 0.00 0.05 0.10 0.25 0.95 1.00

H [eV] 4.97 4.9 4.7 4.0 3.4 3.09 2 −1 D0 [m s ] 0.25 0.4 0.1 0.006 0.07 0.00136

71 Within the framework of Proposal IS380, further data on the Ge diffusion in Si1−yGey will be acquired for the composition regime 0.25 < y < 1.

Experimental Physics Division 95 Biochemistry and Biomedicine

IS348

Mercury ions and organomercurial reagents are extremely toxic due to their affinity for thiol groups. Many + bacteria contain an elaborate detoxification system for a metabolic conversion of Hg2 and organomercurials to non-toxic elemental Hg0. The main components of the enzymatic mercury detoxification are the regulatory protein MerR, the organomercurial lyase MerB, and the mercuric ion reductase MerA (see Fig. IS348–1). The latter protein is a NADPH-dependent flavoenzyme.

merR OP merT merP merA merB merD DNA

Hg(0) Hg(0) Lyase

FAD FAD Hg+

Reductase Cytoplasm

Inner membrane

Periplasm merT

merP Hg(II)

Fig. IS348–1: Model of the enzymatic Hg detoxification system of the plasmid pDU 1358.

The MerR protein, a mercury responsive genetic switch, controls the expression of the other detoxification proteins MerË. MerR exhibits a unique selectivity and ultrasensitivity in stimulating the production of the 2+ −8 MerË (Ë = R, A, B, etc.) proteins: Hg concentrations of 10 M are sufficient to turn on the detoxification system. The molecular origin of the MerR properties is postulated to arise from an unusual mercuric ion coordination environment. In the past we have demonstrated that the measurement of the nuclear quadrupole interaction (NQI) of 199mHg (supplied by the isotope separator ISOLDE) via time differential perturbed angular correlation (TDPAC) is a powerful tool for distinguishing between 2-, 3-, and 4-fold Hg-coordination, and furthermore yields information concerning structural distortions within a given coordination number. Using the 199mHg-NQIs of model compounds as fingerprints we are able to identify Hg coordinations in + + proteins, e.g. in Hg-MerR the Hg2 coordination was identified as 3-fold unambiguously. This quite rare Hg2 + coordination was also detected in the almost inaccessible regime of trace amounts of Hg2 . We also + investigated the binding of the Hg2 -MerR complex to the DNA.

96 Experimental Physics Division Furthermore, we continued to reveal the reaction path of the MerA protein by detecting different Hg coordination spheres via their characteristic NQI signature. MerA is a flavoprotein which uses NADPH (nicotinamide adenine dinucleotide phosphate) as a two-electron reducing agent. It is supposed that the electrons from the NADPH are transferred to one of the four cysteines which constitute together with two + tyrosines the active centre of the protein. In order to gain insight into the Hg2 binding and the pathway of the + Hg2 reduction by the MerA protein, we incubated the native protein and MerA mutants at different 199m conditions in a test experiment with a Hg/Hg(CN)2 solution. In these MerA mutants potential metal ligands, i.e., the cysteines (cys) in the active centre, are replaced partially by the chemically inert amino acid alanine (ala), e.g., the amino acids Cys207Cys212Cys628´Cys629´ (CCCC) can be mutated to Cys207Cys212Ala628´Ala629´ (CCAA).

The indices denote the positions of the cysteines in the amino acid sequence of MerA from Bacillus sp strain RC607. This reduces the number of possible binding sites and allows an assessment of the biological function of each replaced amino acid. The MerA protein binds Hg(II) in three different coordinations (see Fig. IS348–2). Obviously, the 199mHg−NQIs of MerA are forming three different clusters A, B, and C, indicating that MerA binds Hg(II) in three different coordinations: A and B indicate two different 2-fold coordinations, C a tetrahedra 4-fold coordination. The letters and numbers at each data point indicate different experiments. The areas for 2-fold, 3-fold, 4-fold planar, and 4-fold tetrahedral coordinations are motivated by the model compounds. On addition of NADPH, Hg(0) was also found.

160 t Hg(SBu )2 4-foldtetrahedral V Hg(16S4) 2+ 4-foldsquareplanar zz =120 η =0 - V Hg(SPh) 3 3-fold zz Hg(S-Cys) 2 2-fold =100 H04 120 P02 H02 P05 V P38 H10 zz H08 A xx Hg-MerA(CCCC) =80 H15 Hg-MerA(CCCA) V P07 80 Hg-MerA(CCAA) zz P09 =60 P35 P40 P18 V P27 P01 P16

y=-2V P44 zz =40 P12 P24 V B

zz 40 =20

P18 P16 P24 H15 P44 P13 C 0 η =1 0 40 80 120 160 200 240

x=2|2V zz+Vxx|/Sqrt(3) 0 4-fold 3-fold 2-fold Hg 4-fold tetrahedral planar planar linear

Fig. IS348–2: Czjzek diagram of the electric field gradient tensor components 199m Vxx and Vzz of the Hg-NQIs is the MerA protein (CCCC) and its mutants (CCCA, CCAA) together with model compounds for 2-, 3- and 4-fold Hg(II) coordination geometries. The lines from the data points to the η = 0 line depict the changes for decreasing distortions of the first coordination sphere in a modified point charge model.

Experimental Physics Division 97 IS363

Alpha particles show a substantially greater linear energy transfer (LET) than beta particles and as such 149 they are ideal for single-cell killing. Tb (t1/2 = 4.1 h) is a radiolanthanide that decays by electron capture process (76%) accompanied by 17% alpha- and about 7% positron emission. On account of the low alpha energy (< 4 MeV), the maximum range of these alpha particles is only 28 µm in biological tissue. The second major advantage of 149Tb over other alpha emitters is the small positron branching rate, which might be useful to perform an individual in vivo dosimetry for the patient by quantitative PET imaging during the therapeutic procedures. In the present experiments 149Tb was used for labelling of HuM195, a recombinant humanized version of the mouse antibody M195 reactive with CD33 antigen which is expressed on myeloid and monocytic leukemia cells.

The radionuclide 149Tb was produced via proton-induced spallation reaction on tantalum at the online isotope separator facility ISOLDE at CERN. In this process the nuclear reaction products are released from a thick Ta target (120 g/cm2) which is kept at 2200°C during the bombardment with 1 GeV protons. The 2 149 A = 149 isobars were collected on a 200 mg/cm KNO3 backing. The radiochemical purification of Tb from the other A = 149 isobars and from the daughter products accumulated during the collection was achieved by cation exchange (AMINEX A5) chromatography with a-hydroxy-isobutyric acid as eluent in a concentration gradient mode at pH = 5. The Tb-fraction (totally 200 µl) was evaporated to dryness and the 149Tb redissolved in 50–60 µl of 100 mM HCl solution. The 149Tb concentration obtained was 2 GBq/ml. No radionuclide impurities could be detected at the end of the chromatographic purification using high-resolution gamma spectroscopy. The 149Gd containing fractions were combined and purified using the same chromatographic procedure leading finally to a clean carrier-free preparation of 50 µl 100 mM HCl solution of 9MBq 149Gd.

The antibody HuM195 was conjugated with CHX-A-DTPA (cyclohexyldiethylene-triamine-pentaacetic acid). Typically 50 µg of the antibody conjugate were incubated with 1.85 MBq 149Tb in 0.8 ml of ammonium acetate buffered solution for 10 min. Purification and readjustment of pH was achieved by size exclusion chromatography (PD-10 column). The labelling efficiency and radiochemical purity of the final product were measured by ITLC on silica gel strips (SG, Gelman Chem. Co., linear analyser Fa.Berthold) using 0.1 M acetate buffer of pH 5 as a mobile phase. Under these conditions the mAb remains at the origin (Rf = 0) while the free metal ions or its anionic chelates migrate with the solvent front. Similar experiments were performed with 149Gd, the 9.25 d daughter of the 149Tb.

The immunoreactivity of 149Tb labelled CHX-A-DTPA-HuM195 was determined by incubating 2 ng of radiolabelled mAb with a cell pellet of 1 × 107 HL-60 cells for 30 min at 0°C. The cells were washed twice. Supernatants and cells were counted separately. The percentage of immunoreactivity was calculated as the ratio of isotope bound to the cells to the total amount. Measurements of internalization of 149Gd-radiolabelled CHX-A-DTPA-HuM195 was performed by incubating 1 µg/ml radiolabelled mAb with 1 × 106 HL-60 cells for 20 min at 4°C (in the presence of 2% human serum) and assessment of different time points after incubation at 37°C in 5% CO2. Cell pellets were washed twice and then incubated in 1 ml of stripping buffer (50 mM glycine/150 mM NaCl, pH = 2.8) for 10 min at 24°C. The cell-associated radioactivity and acid resistant (internalized) radioactivity were measured and the percentage of total radioactivity was determined. In the cell killing experiments serial dilutions of labelled mAb were added to 1 × 104 HL-60 cells in 0.1 ml in

98 Experimental Physics Division 96 well plates (final activity of 2.6–520 kBq/ml). After incubation ( 5 d at 37°C in 5% CO2), the proliferation capacity was determined by 3H-thymidine incorporation.

The radiolabelling yield of CHX-A-DTPA-HuM195 with 149Tb was almost quantitative (> 96%) after 10 min and the specific activity of 149Tb labelled HuM195 antibodies reached a value of 300 MBq/mg. The radiochemical purity of the final product was better than 98%. The same labelling yields were obtained for 149Gd. Figure IS363–1 illustrates the internalization of the 149Gd labelled HuM195 into HL-60 cells under the described conditions. Further optimization of the conditions is needed, since it has been shown in several series of similar studies that CHX-A-DTPA-HuM195 antibodies labeled with 205/206Bi showed a slightly higher rate of internalization into HL-60 cells.

20 % of con trol cells

10 0 100 200 300 400 Time (min)

Fig. IS363–1: Internalization of 149Gd labelled CHX-A-DTPA-HuM195 in HL-60 cells as a function of time.

In the preliminary HL-60 cell survival studies it could be shown that about 40% of the cells treated with 149Tb labelled CHX-A-DTPA-HuM195 antibodies, were killed (Fig. IS363–2). The highest radiotracer concentration used so far in this experiment was 600 kBq/ml.

120

100

20 (% of con trol cells) H-thymidine incorporation

3 0 1 10 100 1000 Activity (kBq/ml)

Fig. IS363–2: In vitro cell killing efficiency of 149Tb-CHX-A-DTPA-HuM195 for HL-60 cells as a function of activity concentration.

Experimental Physics Division 99 Radiolanthanides generally, and the alpha-emitting lanthanide isotope 149Tb in particular, are well-suited for labelling of CHX-DTPA conjugated monoclonal antibodies. The monoclonal antibody HuM195, chelated with CHX-DTPA and labelled with 149Tb was found to be stable, highly specific, and highly cytotoxic for HL- 60 cells in vitro. These results clearly demonstrate the potential of the alpha emitting 149Tb for nuclear medical applications, and provide further convincing evidence for its potential for targeted alpha immunotherapy.

R&D Projects

RD12 – Timing, Trigger and Control (TTC) Systems for LHC Detectors

The RD12 Common Project now includes representatives from the ALICE, ATLAS, CMS and LHCb experiments, the CERN Microelectronics and Beam Instrumentation Groups and industrial partners. The Collaboration continued the development of a multifunction optoelectronic timing, trigger and control (TTC) distribution system to meet the requirements of the different subdetectors of the LHC experiments and the LHC machine.

During 2000 a high-power laser transmitter was installed at the Prévessin Control Room and connected by optical fibres to a TTC machine interface (TTCmi) at the H2, H4, H8, X5 and X7 test beam areas in the North and West Halls. Each TTCmi can deliver the 40.079 MHz clock with an r.m.s. jitter of less than 10 ps relative to the clock input to the transmitter. In May 2000 the system was used to broadcast the bunch clock and SPS orbit signals when the SPS was operated in a special mode to deliver LHC-structured extracted beams to these areas. Very satisfactory results were achieved by all the participating groups and a further period of running with these special test beams is planned for 2001.

Following a study of the beam synchronous timing requirements for the LHC machine it was decided that, in addition to broadcasting the LHC timing to the experiments, the RD12 system would be used for distributing the timing signals and machine events to the beam instrumentation around the LHC ring and on the PS–SPS and SPS–LHC transfer lines. A representative of the SL Beam Instrumentation Group joined the Common Project and work has commenced on the development of the interface (TTCbi) and software for this additional application.

A family of compact laser transmitters (TTCex etc.) has been developed for encoding and distributing the TTC signals to multiple trigger partitions at the experiments and to the numerous beam instrumentation crates around the LHC machine. Each transmitter can distribute the bunch clock, level-1 trigger, broadcast and individually-addressed commands and data to several hundred destinations via passive optical tree couplers. A batch of 1:32 tree couplers was assembled for the first applications.

Following the results of a questionnaire to users, an upgraded version of the VMEbus interface to the system (TTCvi) was developed. This Mk II version adds additional facilities while remaining largely software-compatible with the first model.

100 Experimental Physics Division The first prototype batch of the DMILL version of the timing receiver ASIC (TTCrx) was received and subjected to irradiation tests with good results. After some modifications had been incorporated to mitigate the effects of SEUs in the associated photodiodes, an engineering run was launched and eight wafers were delivered at the end of the year. The chips were sent for packaging in a new 13 × 13 mm 144 fp BGA package which replaces the 15 × 15mm 100 BGA package used for the initial prototypes.

RD12 continued to contribute to the work on the synchronization of the CMS calorimeter trigger. The work aimed at the design of the final version of the Sync circuit, fulfilling the integration requirements of the CMS calorimeter trigger. The new circuit, which combines two previous prototypes in one single circuit, was developed and successfully tested.

RD18 – Crystal Clear Collaboration

The Crystal Clear Collaboration is an open scientific collaboration, to which any academic group interested is welcome to contribute. The core activity of the Collaboration is on generic developments of technologies to be used in future crystal-based detectors for high-energy physics, medical imaging, and industrial applications. We have very close relations with a number of industrial partners. Among the main achievements in the year 2000 is the start of technology development for the production of LuAP crystals in Russia and Armenia (see Figs. RD18–1 and 2).

Fig. RD18–1: LuAP:CE crystals produced in Armenia.

Fig. RD18–2: LuAP:CE ingots produced in Bogoroditsk.

Experimental Physics Division 101 Besides the generic developments on new crystals and related photodetectors and readout electronics, we organized a number of local centres. Each local centre establishes contacts with the local medical community and obtains the funding to participate in the Crystal Clear project and build a high-resolution small-animal PET scanner for its associated medical centre. The development of the new technology and the design and construction of the new machines are performed in close collaboration between the different centres and the other members of Crystal Clear. At present three such local centres have been set up and funded. In a number of other countries (for instance Switzerland) the creation of similar local centres is being attempted. The situation in each local centre is given below:

1. Flanders Centre: The consortium consists of the Department of radiation detection of the University of Brussels (VUB) the departments of nuclear medicine and pharmacology of Ghent University (RUG), and Janssen Pharma, a research laboratory belonging to the Johnson&Johnson group. This consortium will design and build a small-animal PET scanner optimized for use with rats and mice, and which will mainly be used in new drug development.

2. Rhône-Alpes Centre: This is a consortium between the CERMEP in Lyon, the LETI-CEA in Grenoble, and three institutes from the Crystal Clear Collaboration, namely IPNL (IN2P3) and LPCML from University Claude Bernard and CERN. The consortium will design and build a small-animal PET scanner for the CERMEP in Lyon. The main field of applications is fundamental research in transgenesis and oncology. This scanner will make use of recently developed avalanche photodiodes, and new scintillator materials, to obtain a better spatial resolution and better sensitivity than that achieved in the currently available systems. Moreover, there is an option to combine this micro-PET with an X-ray CT (Computed Tomography) scanner in a multimodal system, in order to have functional activity nodes precisely related to high-resolution anatomical images.

3. Julich Centre: The PrimatePET project is proposed by workgroups of two centres of the Hermann von Helmholtz Association of National Research Centres (HGF centres): Forschungszentrum Jülich and Max-Delbrück-Centrum für Molekulare Medizin, Berlin-Buch, and is approved and funded by the strategy fund of the HGF. The funding period is from July 2000 until June 2003. The aim of this project is to employ the non-invasive PET technique for in vivo investigations of signal transduction under physiological conditions in non-human primates. The analysis of cerebral receptor systems is of outstanding importance for both basic brain research and clinical applications in pathophysiology and pharmacy. In contrast to in vitro techniques, PET permits access to dynamic regulatory processes in the intact body as well as repetitive studies characterizing neurological disorders such as Alzheimer’s and Parkinson’s diseases.

During the year 2000 the main achievements of the Crystal Clear Collaboration were the following:

– Setting up the framework for the organization of the three regional projects, including the definition and sharing of responsibilities, funding, design, and schedule.

– Intensifying the generic R&D on the LuAP:Ce crystal in collaboration with two producers (Ashtarak in Armenia and Bogoroditsk in Russia) to optimize the performance of this crystal as a basic component of the three small-animal PET scanners described above.

– Setting up an ISTC programme (funded by CERN and the European branch of ISTC in Brussels) to develop the mass production technology of the LuAP crystal in Bogoroditsk, including the installation

102 Experimental Physics Division of the necessary infrastructure for the production of the crystals. This project has been approved for the first year.

– Organizing collaboration with Hamamatsu (Japan) for the development of avalanche photodiode arrays for the readout of crystal matrices.

– Setting up six working groups to develop in a coordinated way the main components for the three projects mentioned above. These working groups are on crystal development and production, photodetector development, electronics, software, simulation, and general design.

RD39 – Cryogenic Tracking Detectors

The activities of RD39 have evolved during the year 2000 towards three projects in common with the NA60, COMPASS and TOTEM/CMS experiments. In addition to these, the Collaboration continues the basic research of heavily irradiated silicon detectors at low temperatures, and the development of efficient low-mass cooling systems and detector module construction techniques.

In a common project with NA60, RD39 has designed, constructed and tested a silicon microstrip tracker detector, called the ‘Beamscope’, for the intense primary lead-ion beam of the NA60 experiment. The sensors are segmented into 24 central narrow strips of 50 µm pitch, with four wider strips of 500 µm pitch on each side. Each detector plane consists of two such sensors mounted back-to-back on the front and back sides of a printed circuit board. The PCB has a central hole for the beam, and a heater and thermometer to control the temperature of the sensor. The copper layers of the PCB were designed to provide a reasonable heat leak to the vacuum flange through which the board goes. This feedthrough was made hermetic by gluing with a special epoxy that withstands thermal shocks.

The Beamscope was exposed for 42 days to the high-intensity Pb-ion beam of the SPS, delivering an average of 7 × 107 ions in 4.5 s bursts through the detector. The fluence was estimated by measuring the beam intensity and normalizing to the fraction of beam passing through the Beamscope planes. In the most exposed region the fluence was (5 ± 2) × 1014 Pb ions/cm2, which corresponds to a total energy loss of 90±40 Grad. While the conversion of this unprecedented energy deposit to an equivalent neutron fluence is not known yet, it is clear that the detector was operational at 130 K temperature at the end of the run, and that operation at higher temperature was impossible because of the very large leakage current owing to the record damage of the bulk silicon. Figure RD39–1 shows the Beamscope tracker module which features a cooling pipe of 1.2 mm diameter, soldered directly on the PCB, and vacuum feedthrough.

Fig. RD39–1: The NA60 Beamscope tracker module.

Experimental Physics Division 103 RD39 is also developing low-temperature silicon microstrip tracker modules in collaboration with the TOTEM experiment. These detectors will be mounted in the Roman pots and will be used for tracking the protons of forward elastic-scattering events in the experiment at LHC. The smallest momentum transfer requires tracking at a distance of a few millimetres from the LHC beam. The measurement of the total cross- section requires the simultaneous measurement of the event rates due to the total and the forward elastic cross- sections: this luminosity-independent technique is based on the optical theorem and the extrapolation of the forward elastic-scattering amplitude to zero momentum transfer. The accuracy of the experimental total cross- section depends critically on how small-momentum transfers can be observed, because the functional form of the extrapolation is not known from theory, and because the ratio of the real and imaginary parts of the amplitude can only be estimated from the data at these very small momentum transfers. This ratio contributes to about 5% to the magnitude of the total cross-section, and since the goal is an accuracy of better than 5%, it is obvious that the closest approach to the beam is desirable in the experiment. This requires an edgeless detector that has no dead material on its side facing the beam, apart from a thin metallic window providing vacuum and RF isolation between the machine and the detector. The by-product of the luminosity-independent measurement of the total cross-section is the measurement of the luminosity itself, and the calibration of the simpler monitoring devices and techniques which can be operated up to the maximum luminosity of the LHC.

For these Roman pot tracker modules RD39 develops edgeless silicon detectors which are sensitive to minimum-ionizing particles traversing the sensor at its physical edge near the beam. This excludes the use of a guard ring at that edge, and requires a very small surface current. Preliminary results prove that the edge current of a suitably treated edge surface has a similar steep temperature dependence as the bulk current, and therefore the operation of the sensor at about 130 K solves the problem of the edge sensitivity, while at the same time providing hardness against 10 times more radiation than the present state-of-the-art silicon sensors operated close to room temperature. Further work is under way, which should result in edgeless detectors that can be operated at a few hundred volts with nA current at low temperatures.

The TOTEM experiment runs at low luminosity, which is obtained by reducing the number of bunches in the machine, and by increasing the beta function of the machine optics at the intersection point. Although the elastic event rates required by the experiment are such that no substantial damage can be expected during the few months of data taking of TOTEM, the background radiation in the Roman pot areas during high- luminosity operation can be so high that the sensors and readout electronics need to be radiation-hardened, in particular if new luminosity measurement or calibration is required after several years of operation at a high luminosity.

RD39 is developing, with the COMPASS experiment, silicon microstrip tracker modules which will be used in the high-intensity muon beam of the SPS, for recording deep inelastic events in the beam region after the target of the experiment. The predicted fluence through the sensors is higher than that of the innermost trackers of the LHC experiments after 10 years, and therefore the detectors must operate at low temperatures in order to profit from the Lazarus effect. The microstrip sensors will be read out by APV25 chips developed by CMS; the readout chip was tested down to 80 K temperature and was found to be operational.

The basic device physics and modelling studies, as well as the measurements of the recovery of charge collection at low temperatures (the Lazarus effect), were continued in order to be able to make reliable predictions for the radiation resistance of silicon detector devices. Operation at forward bias was shown to be

104 Experimental Physics Division a viable solution, and new detector structures were developed. Among these the symmetric p+np+ structure gave very promising results.

In the year 2000 RD39 also started the development of efficient cooling systems and module micro- assembly techniques, in view of the application of the low-temperature detectors in large tracker arrays and in high-radiation areas with limited access. A test bench was built for measuring the basic engineering parameters in two-phase flow of suitable coolants such as Ar and N2.

RD42 – Development of Diamond Tracking Detectors for High-Luminosity Experiments at the LHC

NIKHEF, Amsterdam; CERN; The Ohio State University, Columbus; Faculty of Physics and Nuclear Techniques, UMM, Cracow; GSI Darmstadt; LENS and University of Florence; FNAL; LETI (CEA- Technologies Avancées) DEIN/SPE - CEA Saclay Gif-Sur-Yvette; II.Inst. für Exp. Physik, Hamburg; MPI für Kernphysik, Heidelberg; CPPM Marseille; INFN and Polytechnico Milano; Rutgers University, Piscataway; Carnegie-Mellon University, Pittsburgh; LEPSI, IN2P3/CNRS-ULP, Strasbourg; Univerity of Torino; University of Toronto; Institut für Hochenergiephysik der Österr. Akademie der Wissenschaften, Vienna.

The RD42 Collaboration (see http://www.cern.ch/RD42) is developing chemical vapour deposition (CVD) diamond detectors for tracking applications for experiments at the LHC detectors based on CVD diamond which may be a radiation-hard option for pixel and strip detectors very close to the interaction region in the experiments.

The high quality diamond, grown in a chemical vapour deposition process by industry, can be used as a charged particle detector. The diamond material is processed to a final thickness and size depending on the application. For CVD diamond detectors from production reactors, charge collection distances of 220 µm are now possible, corresponding to a mean charge collected of 8000 e. Irradiation with pions, protons and neutrons at room temperature indicates that diamond sensors can resist higher fluences than silicon devices. After irradiation the shape of the signal distributions is narrower than before, and entries in the tail of the distribution appear closer to the most probable signal. The low end of the pulse height distribution changes very little. The spatial resolution improves after irradiation.

Work on bump-bonded diamond pixel detectors with geometries required for the ATLAS and CMS readout chips is in progress, in collaboration with groups from both experiments. Figure RD42–1 shows two photographs of top views onto the pixel patterns of CVD diamond detectors prepared for the ATLAS and CMS pixel readout. After bump bonding to the pixel readout the detectors were tested in particle beams. Results are reported in the status reports CERN/LHCC 2000–011, 2000–015, and 2001–002.

Experimental Physics Division 105 Fig. RD42–1: Photograph of the top view of an ATLAS (left) and CMS (right) diamond pixel sensor showing the pixel pattern.

RD45 – Object Persistency

The RD45 project made its last status report to the LHC Computing Board (LCB) in November 1999. Pending the review of LHC Computing, which took place during the course of 2000, the LCB was suspended. During 2000, an RD45 workshop was held, at which performance and scalability measurements of the Espresso proof-of-concept prototype were presented. A final release of this prototype was made at the end of 2000, enabling a manpower estimate to be made for producing a full product. The final report of the review of LHC Computing recommended that the RD45 project be considered terminated, whilst nevertheless recommending the initiation of a Technical Access Group in the area of Data Management.

RD48 – Radiation Hardening of Silicon Detectors

Silicon detectors will be widely used in experiments at the LHC, where high radiation levels will cause significant bulk damage. In addition to increased leakage current and charge collection losses worsening the signal-to-noise ratio, the induced radiation damage changes the effective doping concentration and represents the limiting factor to long-term operation of silicon detectors.

The objectives of RD48 were to develop radiation-hard silicon detectors that can operate beyond the limits of the devices present at the approval of RD48 in 1996, and that ensure guaranteed operation for the whole lifetime of the LHC experimental programme.

Float zone (FZ) silicon materials with addition of oxygen, carbon, nitrogen, germanium and tin were produced, as well as epitaxial and Czochralski (CZ) silicon materials. Their impurity concentrations were measured using SIMS and IR techniques. Single pad diodes were manufactured from these non-standard materials using either a planar or a mesa process. Their electrical and energy level defect characterization was performed before and after irradiation. Radiation-induced defect modelling and experimental results showed that the silicon radiation hardness depends on the atomic impurities present in the initial monocrystalline material.

106 Experimental Physics Division The RD48 (ROSE) Collaboration successfully terminated its programme at the end of 2000. With the development of the Diffusion Oxygenated Float Zone silicon (DOFZ) a good improvement of the radiation hardness was achieved. The main results can be summarized as follows:

– For charged hadron irradiation the damage-induced changes of the effective doping concentration, directly correlating with depletion voltage, can be substantially improved by oxygenation. A hardening effect by a factor of 3 was established for the annealing independent term. In addition the reverse annealing amplitude saturates at high fluences, amounting to a reduction factor of up to 3 for DOFZ diodes. The time constant involved is larger by a factor of 2 at least. Thus both effects provide a substantial safety margin for the effects to be expected during the warm-up maintenance periods.

– Though for MeV neutron irradiation a radiation hardening effect equivalent to that established for charged hadrons is absent, it was verified that the use of low resistivity silicon is beneficial.

– The Hamburg model for parametrization of the damage and annealing behaviour is verified also for O- enriched silicon. Simulations for the full 10-year LHC operational scenario were made for both the ATLAS pixel and microstrip layers. It was shown that even the pixel sensor for the B-layer (at a radius of 4 cm), if produced with DOFZ silicon, will withstand the full 10-year LHC operational period.

– The DOFZ technology has proven to be both technologically feasible and cost effective. The transfer to major European detector manufacturers was successful. Diodes produced in this way show superior radiation hardness.

– Up to now the ATLAS Pixel and part of the ATLAS SCT group have decided to use the DOFZ technology.

RD49 – Study of the Radiation Tolerance of ICs for the LHC

LAPP Annecy, BNL, CEA, CERN, CNES, Faculty of Physics Cracow, DESY, ESA ESTEC, Fermilab, IST Lisbon, IMEC Leuven, Brunel University London, Cyclotron Research Center Louvain-La-Neuve, Faculty of Physics Madrid, University of Montreal, University of Montpellier, University of Padova, University of Rome II, LEPSI-IRES Strasbourg, Institute of Physics Prague and INFN Torino.

In 2000 the RD49 Collaboration completed the study of the radiation tolerance of the quarter micron technology, and has continued to disseminate the radiation tolerance know-how in the LHC community. The innovative technique of radiation-tolerant integrated circuit design, developed by RD49, has been successfully taken up by many other institutes. The use of commercial-grade quarter-micron CMOS processes with adapted mask layout techniques is so effective and reliable that it has attracted a considerable interest, and a large number of complex ASICs have been successfully developed within the LHC community, demonstrating the maturity of the radiation-tolerant method. Several LHC experiments are now developing their new radiation-hardened ASICs or back-up radiation-tolerant version of previous ASIC circuits originally developed in hardened technologies. Owing to the lack of availability of radiation-hardened technology, the radiation-tolerant approach turns out to be the only viable solution for the development of hardened ASICs in the future. To facilitate the increasing demand to develop and manufacture radiation-tolerant circuits, a four- year contract with a major semiconductor manufacturer was signed, and the export license required for employing this advanced technology has been successfully obtained. To support LHC design teams, Multi- Project Wafer runs have been organized in which prototypes of 60 different designs were produced.

Experimental Physics Division 107 The Collaboration has directly contributed to the development of the following radiation-tolerant ASICs:

– a pixel readout chip (ALICE1) for the ALICE pixel detector and the LHCb RICH detector;

– a 32-channel readout chip (PASCAL) in collaboration with INFN Torino for the ALICE Silicon Drift Detector (SDD) readout;

– a fast, low-noise, preamplifier-discriminator circuit (CARIOCA) for the LHCb muon detector readout in collaboration with Rio de Janeiro;

– a fast, current-sensitive, low-noise, 32-channel amplifier for the NA60 proton beam hodoscope.

After having completed the noise characterization of deep submicron processes in 1999, the Collaboration continued in 2000 the characterization of the analog performance by studying the matching characteristics of the quarter-micron technology currently used to develop radiation-tolerant circuits. Matching performance is particularly important for LHC multi-channel front-end systems for which channel uniformity in gain and offset voltage is a crucial characteristic for the front-end performance. The threshold voltage and the current factor matching of p-channel and n-channel transistors were measured before irradiation and after 1.5 Mrad

(Si02). Results of the statistical analysis of the threshold matching are shown in Fig. RD49–1. Matching measured on p-channel transistors shows that the experimental value of the threshold voltage matching parameter, 3.7 mV µm r.m.s., is close to the lowest limit predicted by statistical dopant fluctuations of 2.5 mV µm r.m.s. (calculated for a gate oxide thickness of 5 nm). This value is practically unchanged after irradiation. Enclosed n-channel transistors used for hardening designs have about the same matching value as p-channel devices before irradiation. The value of enclosed n-channel after irradiation is increased to 5.4 mV µm r.m.s.

3 5 prerad prerad pl 4. 3 / 0. 28 4.5 postrad 2.5 post rad 4 ne 0. 76 3.5 2 ne 25 / 0.5 pl 5. 2 / 0.5 3 [mV] 1.5 [mV] 2.5 Vth Vth 2 1 1.5 ne 4. 74 pl 11.2 / 2 1 0.5 0.5 pl 23.2 / 5 0 0 0 0.1 0.2 0.3 0.4 0.5 0 0.2 0.4 0.6 0.8 1 1.2 (Gate Area )-1/2 [1/µm](Gate Are a)-1/2 [1/µm]

∆ Fig. RD49–1: Threshold matching Vth before and after irradiation for the enclosed n-channel transistors (left) and for the p-channel transistors (right). Each point of these plots is obtained by measuring 90 transistor pairs

The Collaboration performed a preliminary study of the characteristics of the quarter-micron technology at low temperature. A fast, current-sensitive preamplifier developed by RD49 in 1999 was tested from room temperature to 4.2 K. Preliminary results show that down to 20 K the amplifier is functional although its

108 Experimental Physics Division biasing regime changes substantially. For operation at 77 K, which is the cryogenic temperature used in most of the foreseen applications, the amplifier exhibits a significantly faster rise time and a lower noise.

For the radiation qualification of ASICs and Commercial-Off-The-Shelf (COTS) components, the Collaboration has reached an agreement with the Cyclotron Research Center (CRC) in Louvain-la-Neuve (Belgium). LHC users benefit from preferential conditions for access to the Cyclone cyclotron in order to perform proton irradiation with beams optimized for the study and measurement of single-event effects in integrated circuits. In October the first irradiation campaign was coordinated at Cyclone, in which five different LHC groups participated. Irradiation campaigns were also organized in the 300 MeV proton and 200 MeV pion beams of the Paul Scherrer Institute. The education of the LHC community on the risks associated with the use of COTS in the LHC radiation environment was continued. This was done with workshops within CMS and LHCb, and a training course organized in collaboration with the CERN Education Service, which attracted an attendance of more than 100 participants from the experiments and the LHC machine.

In order to develop a radiation qualification procedure for bipolar components including the Enhanced Low-Dose-Rate (ELDR) effect, which is responsible for early failure, a study was performed to define an accelerated radiation test protocol. The basic principle of the accelerated radiation test is to perform an irradiation at elevated temperature, which simulates the low-dose-rate condition in thick oxide of bipolar circuits where the ELDR effect takes place. A series of experimental tests based on the measurement of the excess base current has established the optimum temperature cycle.

In collaboration with ST Microelectronics (Italy) a prototype, radiation-hardened, negative-voltage regulator, L7913, intended for the LHC experiments, was fabricated and tested. A final prototype is scheduled for delivery in April 2001 together with the final positive-voltage version L4913.

Other Experiments

CAST

Previous solar axion searches were carried out in Brookhaven (1990) and in Tokyo (2000), tracking the Sun with a dipole magnet. The solar neutrino anomaly amply demonstrates that the Sun is a very useful source of weakly interacting particles for fundamental research. Axions would be produced in the Sun’s core through the scattering of thermal photons in the Coulomb field of electric charges (Primakoff effect). In a transverse magnetic field the Primakoff effect can work in reverse, converting coherently the solar axions back into X- ray photons of a few keV. The conversion efficiency increases with (B ⋅ L)2. An LHC dipole prototype (B = 9 T and L = 10 m) with straight beam pipes provides a conversion efficiency exceeding that of the two earlier solar axion telescopes by almost a factor of 100.

In the CAST experiment an LHC magnet will be mounted on a moving platform (Fig. CAST–1) and coupled to either gas-filled or solid-state, low-background, X-ray detectors on either end allowing it to observe the Sun for half an hour at sunrise and half an hour at sunset. The rest of the day will be devoted to background measurements and, through the Earth’s motion, to observations of a large portion of the sky.

Experimental Physics Division 109 Fig. CAST–1: Schematic view of the CAST detector.

The ~50 mm aperture of the LHC magnet’s beam pipes requires correspondingly large X-ray detectors, implying a large level of noise. To overcome this problem, the CAST Collaboration is considering using an X- ray mirror system, to focus the converted X-rays emerging parallel from the magnet to a millimetre-sized spot (Fig. CAST–2). This will bring a significant signal-to-noise improvement over the original CAST proposal and the earlier solar axion telescopes. An option to recover a module constructed for the German orbiting X- ray telescope ABRIXAS is currently being pursued.

Fig. CAST–2: Schematic view of the X-ray mirror.

CAST has the potential to reach a detection sensitivity for axions about ten times higher than that of the previous solar axion telescopes, extending for the first time the axion searches beyond the limit dictated by astrophysical considerations (Fig. CAST–3).

110 Experimental Physics Division Fig. CAST–3: Sensitivity of the CAST detector.

EXPLORER

EXPLORER is a cryogenic resonant-mass gravitational wave (GW) detector realized and operated by the ROG Collaboration (CERN, INFN Frascati, INFN and Univ. of Rome1 and Rome2, CNR-IFSI and IESS, Univ. L’Aquila). It has been in operation at CERN since 1984 and was the first cryogenic GW antenna to perform continuous observations (since 1990).

EXPLORER is part of the international network of resonant-mass detectors which includes ALLEGRO at the Louisiana State University, AURIGA at the INFN Legnaro Laboratories, NAUTILUS at the INFN Frascati Laboratories, and NIOBE at the University of Western Australia.

At the beginning of the year 2000, EXPLORER was upgraded and is at present the most sensitive gravitational wave detector in continuous operation. The minimum detectable spectral amplitude is better than − − 10 20 m/Hz 1/2 over a frequency band of 50 Hz around 900 Hz. The corresponding sensitivity to short GW − bursts is h = 2 × 10 19. This sensitivity should allow the detection of signal from gravitational collapses and from coalescing and merging neutron stars/black holes binaries in our Galaxy and in Local Group.

The EXPLORER detector consists of an Al5056 cylindrical bar with length L = 3 m, diameter of 0.6 m and mass of 2270 kg, resonating in its first longitudinal mode of vibration at a frequency of about 900 Hz. The cylindrical bar is suspended in vacuum inside a cryostat and is kept cold at a temperature T = 2 K by a superfluid helium bath surrounding the bar vacuum chamber. The isolation of the bar from external acoustic and seismic disturbances is provided by a system of low-pass mechanical filters in cascade, with a total attenuation of −210 dB around the antenna resonance frequency.

The vibrations of the bar are converted into electrical signals by a capacitive transducer resonating at the antenna frequency in order to improve the energy transfer from the bar to the electronics. The signals are

Experimental Physics Division 111 applied to the input coil of a dc SQUID amplifier by means of a superconducting transformer, which provides the required impedance matching. The transducer and the bar form a system of two coupled oscillators with − + frequencies f = 888 Hz and f = 922 Hz. The output signal from the SQUID instrumentation is directly sent to the acquisition system, together with the timing information. The detector is also equipped with auxiliary sensors (accelerometers, search coil, etc.) that monitor the environment of the laboratory and allow the veto of any event, observed by the detector, that occurs in the presence of external disturbances. The detector duty cycle is about 80% on account of cryogenic operations and maintenance. Absolute calibrations of the EXPLORER detector were performed using the sinusoidal gravitational near field generated by a rotating quadrupole.

The recent EXPLORER upgrade concerned both the vibration isolation system and the readout. In March 2000 the experiment started to operate in the new configuration obtaining a significant improvement in sensitivity and stability. The new capacitive resonant transducer (with a gap of about 10 mm) and the new Quantum Design dcSQUID led to a remarkable improvement of the performance: a detector noise temperature of about 2 mK and a bandwidth of about 10 Hz were obtained. The present bandwidth is one order of magnitude larger than that of the other operating resonant detectors.

In addition to hosting the most sensitive GW detector, CERN is also the site where the data from of all the five operating detectors are stored: during the year 2000 a database of all the GW events data (since 1997) was implemented in collaboration with the CERN Oracle Support Group. For more details see: http://cern.ch/db/oracle/casestudies/welcome.html

Technical Developments

Engineering and Construction Group (EC)

ATLAS. The group is in charge of the mechanical integration of the detectors, of the layout and design of the central rails and support structure, of the detector’s displacement systems, and of the layout and integration of the muon detection system in the barrel magnet and forward region. For the MDT drift tubes of the muon detector the Group participated in the final design, construction, and tests of new end plugs based on ‘twisters’ as precision wire locators, leading to a new wiring procedure with a high degree of automation. Two additional wiring automatons were built, one for NIKHEF (Amsterdam) and the other for Freiburg (Germany). Constant mechanical support is given to the tile calorimeter modules, instrumented at CERN, and for the tests and the assembly of the components and modules of the liquid argon calorimeter. The Group participates in the definition and specification of the electrical power equipment for the three superconducting magnet systems. The installation of the magnet test facility in hall 180 is continuing. Tests on the cryogenic current leads (B00) have started. Tests on the coil B0 will soon follow.

CMS. The group participates in various working groups on engineering and integration, experimental areas, cooling, services, and infrastructure. The group designed the ‘Ferris wheel’, a large handling device for the assembly of the magnet rings. It is now installed in the CMS surface hall and the series assembly of the magnet rings by industry has started. The group continues its work on the silicon microstrip detectors for the forward/backward tracker of CMS.

112 Experimental Physics Division LHCb. The group participates in design work on the layout and implementation of the detector in its experimental area. Engineering support in the development, layout, and testing of the muon chambers continues. The detailed design of the large dipole magnet with resistive coils progressed. Invitations to tender were sent out for the aluminium conductor, the coils and the iron plates of the yoke, and firms were chosen for their production. Bending tests to verify design requirements for the resistive coils of the ALICE and LHCb magnets were performed with the foreseen conductor dimensions.

Magnetic fields. For the EP division, the group is in charge of the repair, modification, and installation of most of the experimental magnets (except for ATLAS, CMS and ALICE). For the HARP experiment the group re-arranged the dipole magnet (Orsay magnet) and increased its gap. The solenoidal TPC90 magnet was prolonged by 50 cm. For this magnet the group produced and installed 20 additional double pancakes. These modifications were optimized by field map calculations with the TOSCA program. Both magnets were installed in the experimental area and their field measured. The group also measured the field of the bending magnet of the WA103 experiment. The ALICE and LHCb magnet designs were supported by calculations of the field and electromagnetic forces with the TOSCA and POISSON programs and by calculations of the electromagnetic and thermal stress in the coils by ANSYS. Work continues to develop small precision cubes equipped with Hall probes to measure vector field components. The cubes will be used for new measuring equipment and in large number for the measuring and monitoring of the ATLAS barrel magnet.

The MISTRAL experiment at the ISOLDE facility received support in the layout of a new radiofrequency modulator; the nTOF and CAST experiments received design support.

Restructuring plans of the technical support sector finally led to the merging of EC group with EOS group and others into a new TA3 group at the end of the year.

Technical Assistance Group TA1

During 2000 the group, while still committed to the ATLAS and CMS inner trackers, extended its support to HARP. The Thin Films and Glass Section continued its activity of general service and support for ALICE (CsI photocathodes), COMPASS (CsI and RICH), and the Hybrid Photo-Detectors (HPD). The TA1-GD section pursued work on the Gas Electron Multiplier (GEM) detectors, and Triple GEM chambers for the COMPASS tracker were assembled.

In year 2001 TA1, following the re-organization of the support groups after the shutdown of LEP, will incorporate two new sections: (a) the Gas Systems Section (GS) consisting of the former gas sections of ALEPH and DELPHI, (b) the Solid-State Detector Section (SD), which incorporates the former bonding facility of OPAL, the irradiation facilities of MIC, and the Thin Film Section of TA1.

CMS Inner Tracker. The major decision of CMS at the end of 1999 to abandon the MSGC solution for the outer tracker in favour of a full silicon tracker considerably influenced the work of TA1. While keeping the mechanical solution for the outer barrel, the major effort went in two directions: (a) the re-design of the support structure to host the ladders of silicon detectors, (b) the design up to its completion, including all the services, of a ladder of silicon modules. The internal review of the tracker, for the work done by TA1, was successfully passed in autumn.

Experimental Physics Division 113 ATLAS Transition Radiation Tracker (TRT). Inside the tracker project for ATLAS, TA1 continued its major responsibilities for the design and construction of the TRT forward prototypes as well as in the integration and assembly of the full detector.

During 2000 a complete tooling for the construction of a wheel was built and tested by assembling a second complete four-plane prototype. The design of the final end-cap wheels together with the assembly tooling is almost completed. Considerable support (visits to the two sites and procurement of all tooling and parts) was supplied to PNPI and Dubna to allow the start-up of production in Russia: the reinforcement of straws for the USA sites and some pre-production of straws (preparation for the assembly of wheels). In parallel, the design of the services and integration of the tracker for the ATLAS detector progressed considerably.

HARP. Besides the technical co-ordination and general technical support, the main role of TA1 was the design and some prototyping for the TPC, which has taken an increasing importance in the activity of the whole group.

Emulsions and Scintillator Section. The group continued to be responsible for the emulsion pouring and development facility. In spite of the fact that the working area had been reduced, repair and provision of new scintillators was maintained at the same level as before.

Thin Films and Glass Section. The section provides technical support for thin film coating and machining of glass and ceramics. During 2000, in addition to basic service, specific contributions to the RICH detectors for ALICE and COMPASS were made. For COMPASS, after completion of a large-area photocathode production plant, the section produced most of the cesium-iodide photosensitive layers to be installed in the RICH detector. The section also helped in the purchase of 125 VUV glass mirrors. In addition, it provided fundamental assistance for the operation of the VUV reflecto-meter to qualify the production of these mirrors. Strong support was given to the LHCb team for the development of a novel large-area HPD. This activity, given its R&D potential, will continue regardless of the choice of LHCb. In 2001 the Thin Film Section will be merged into the new SD section.

Gas Detectors Development. The main activity of the TA1-GD section in 2000 continued to be the development of the GEM concept. Measurements performed in the laboratory and in the beam have contributed to the final design of the chambers for the COMPASS tracker. Several large-sized triple-GEM detectors (32 × 32 cm2 active) were built and tested. Furthermore, advice and technical support were given to many potential users for a wide range of applications.

Technical Assistance Group TA2

During 2000 the group collaborated with and provided technical assistance to several experiments. The collaboration with LHC experiments was extended; the group was still able to keep the level of support for LEP and fixed-target experiments as in previous years. The group is also responsible for the EP divisional Composite Material Laboratory. This facility is available for further use.

The group collaborated with the DELPHI experiment at LEP in the area of technical co-ordination and had the operational responsibility for the RICH detectors. The detectors were operated for about 230 days in 2000

114 Experimental Physics Division with full efficiency and excellent data quality. An increased effort was required to keep the ageing detectors and their electronics fully operational. The work to decommission the detectors in November 2000 went very well and will be terminated in summer 2001. The technical co-ordination of DELPHI also encompassed the overall co-ordination of the dismantling of the four LEP experiments. It includes safety aspects, logistics, INB-related questions, and material sales.

Fixed-target experiments. The group collaborates with COMPASS-NA58 in the fields of technical co- ordination, integration, and the installation of the experiment. The group is also involved in the COMPASS RICH project, particularly in the study of the quality of mirror prototypes and of the stability of the mirror mounting and alignment mechanics as well as in the installation of the mirrors in the RICH 1 vessel. The gluing of the frames and quartz windows of the photon chambers were carried out with support of the group.

The group is collaborating with three of the LHC experiments:

ALICE. Technical co-ordination of the ALICE experiment was within the group. Support is provided for the general design of the experimental apparatus. The group collaborated in the conception of the field cage for the ALICE TPC. This included mechanical and thermal analysis. A market survey was launched on the basis of this design and has led to responses from potential manufacturers in Europe. The field cage prototype work included the installation of the composite field cage prototype structure into an aluminium containment vessel, the assembly of the entire electrostatic network, and the installation of a readout chamber. The TPC prototype fulfilled the milestone towards the final product definition. The group is also involved in the final design of the HMPID detector as well as in the fabrication of several prototypes of the pad plane photocathodes. Preparation of tooling for the production of these photocathodes has started. Test beam support was also provided.

CMS. The support for the CMS experiment was concentrated on the Pre-shower Detector. During 2000, the main design effort went into services and feedthroughs. The tooling for the fluxless brazing of the aluminium cooling screens was finalized. Another major effort for the group was the engineering review of the detector, successfully passed in the Autumn of 2000.

LHCb. The collaboration with the LHCb experiment was concentrated around the RICH detectors. The group was involved in the choice of the photon detector, the Pixel Hybrid Photo-Diode (HPD), and in the RICH2 structure and optical systems. The Pixel HPDs are developed in close collaboration with industry. Full-scale prototype tubes encapsulating a 1024-pixel detector bump-bonded to a binary readout chip are in preparation. A first version of this chip, designed within the CERN MIC and ED groups as a collaboration between ALICE and LHCb, was manufactured and is currently under tests. For specific vacuum-tube applications, the group developed with industry a custom ceramic carrier onto which the chip was mounted and wire-bonded. The group participated in the development of an interface card for the electronic readout of this chip. The behaviour of Pixel HPDs and their associated mu-metal shields in low magnetic fields was also measured and simulated. The conceptual design of the RICH2 structure was completed and the guidelines for construction and alignment procedures are being defined. Progress in the definition of mirror specifications was made and first prototypes were produced by collaborating industries. The optical test laboratory is fully operational.

Experimental Physics Division 115 Generic research and development. The group continues to support R&D work on the ISPA tube and the Pixel HPD for biomedical applications. We are also collaborating for a specific pixel chip design for low- energy electron detection. The continuing effort of the group in the development of the Pad HPD led to the fabrication of several sealed devices with silicon sensor and encapsulated VA2 electronics. The photocathode processing and the indium sealing technique are now mastered. Several Pad HPDs were successfully tested in beam set-ups.

Microelectronics Group (MIC)

The microelectronics group collaborated closely with detector builders and electronics system designers from CERN and other institutes on developments for the front-end electronics, readout, and control of detector systems for the four LHC Collaborations and for the NA60 heavy-ion experiment. In parallel, the group essentially achieved all the goals of its R&D work on the radiation hardening of silicon detectors (RD48) and the development of design techniques to enhance the radiation tolerance of CMOS ASICs for LHC applications (RD49).

R&D projects. The RD48 project, which had developed a method for the radiation hardening of silicon detectors by diffusing oxygen into the silicon bulk during the detector manufacturing process, was successfully terminated. Several manufacturers incorporated oxygen diffusion as an optional step in their process flow. Silicon detectors hardened by oxygen diffusion will be used in the ATLAS pixel detectors and are also under consideration by other LHC detector groups. Continuous support was given to proton and neutron irradiation facilities developed previously by the group at the CERN SPS. At the end of the year the staff involved in these activities was transferred to the new Solid-State Detector support section TA1-SD.

During the year the group saw its innovative technique of radiation-tolerant integrated circuit design, developed in the RD49 project, taken up by many other institutes. The adoption of the method, which is based on the use of commercial-grade deep sub-micron CMOS processes and unconventional mask layout techniques, was facilitated by the negotiation of a four-year contract with a major semiconductor manufacturer for foundry services in a 0.25 µm CMOS process. The export licences required for this advanced technology were obtained and, to support the LHC ASIC development community, the group organized multi-project wafer runs in which prototypes of 60 different designs were produced for users inside and outside CERN. In collaboration with the Rutherford Appleton Laboratory (RAL) the group dedicated much effort to the further development, distribution, and support of the special design-kit and library required for radiation-tolerant design. A considerable effort was also expended on transferring radiation-tolerant design methods to other institutes.

In the framework of the RD49 project, promising results from the Active Feedback Preamplifier (AFP) chip operating at cryogenic temperatures were obtained. At 100 K the AFP preamplifier exhibits a pulse − peaking time of 5 ns with a noise level of about 300–500 e r.m.s. for a detector capacitance of 5 pF. For the NA60 experiment a 32-channel AFP chip is now under development for the readout of the proton beam cryogenic silicon strip hodoscope.

ALICE and LHCb. In collaboration with the University of Turin, radiation-tolerant demonstrators of an analog memory and a 10-bit 4 MS/s ADC, developed by RD49, were incorporated into a complete front-end readout system on a chip (PASCAL) for the ALICE Silicon Drift Detector (SDD). The PASCAL chip

116 Experimental Physics Division (Fig. Tech–1, right), developed in the 0.25 µm process, contains 32 channels of low-noise amplifiers, a 256- cell deep analog memory, 16 A-to-D converters, and digital back-end logic. Preliminary characterization of − the prototype showed full functionality with an excellent noise performance of the front-end (ENC = 300 e r.m.s.). For the ALICE time-of-flight detector, the group prototyped an 8-channel TDC ASIC with a resolution better than 50 ps.

For the ALICE HMPID RICH detector, the pre-production of the Gassiplex chip in 0.7 µm CMOS technology was launched and a high yield was measured on a total of 2000 chips. Also for the HMPID detector, a prototype of the sparse data-scan chip Dilogic was successfully tested.

The main activity for the development of pixel detectors for ALICE and LHCb was the submission and initial characterization of the ‘ALICE1-LHCb’ chip (Fig. Tech–1, left). Probably the largest mixed-mode ASIC ever attempted in the HEP community, it was designed using the RD49 radiation-tolerant approach and contains around 13 million transistors and uses six metal layers. The chip contains 8000 identical pixels, each measuring 50 microns × 425 microns and has operating modes either for the ALICE silicon pixel microvertex tracker, or for the LHCb RICH detector readout. Initial tests indicate that the chip functions well, although at a lower maximum clock frequency than predicted by simulation. Characterization continues with the ALICE and LHCb teams.

For readout of the LHCb muon detectors, a novel current-mode feedback amplifier was developed in collaboration with the Instituto de Física, Rio de Janeiro. This CARIOCA chip, also designed and fabricated in the 0.25 µm process using the radiation-tolerant technique, is an 8-channel prototype and includes a current- mode discriminator. Measurements show that the performance meets the specification for the LHCb muon − detector. Noise performance is excellent with an ENC of 2000 e r.m.s. for a detector capacitance of 40 pF.

Fig. Tech–1: ALICE 1 LHCb chip, die size is 13.6 mm × 15.9 mm.

Experimental Physics Division 117 ATLAS. The ABCD chip, developed jointly with Cracow, the University of Geneva, and RAL was chosen by the ATLAS Silicon Central Tracker (SCT) collaboration as the baseline for their front-end readout. Twelve chips mounted on prototype barrel modules (1536 channels per module) have shown satisfactory operation and meet specifications. Minor design changes were carried out to improve the radiation hardness of the ABCD3T chip. An automated wafer probing system, developed together with Valencia University, was used to evaluate the pre-production wafers.

The DTMROC chip developed for the readout of the ATLAS TRT detector in collaboration with the University of Geneva, the University of Pennsylvania, and Cracow was manufactured, tested and mounted with the prototype TRT wheels. Experimental results obtained were very satisfactory. Work on the final version of the DTMROC design was started and includes modifications to improve timing performance, and to add control DACs for the companion front-end bipolar chip (ASDBLR).

CMS. For the CMS tracker a number of ASICs are in an advanced state of design or ready for submission for prototype manufacturing in the 0.25 µm technology. The CCU25 is the radiation-tolerant network controller ASIC used in the on-detector timing distribution and embedded slow-control electronics. The DCU is an embedded 8-channel, medium-precision, slow, low-power, radiation-tolerant ADC for embedded detector monitoring functions. A number of ancillary radiation-tolerant chips were also designed and prototyped, such as special-purpose LVDS buffers and a receiver for the 40 Mbit/s digital optical link. An analog laser-driver ASIC was also developed and is under evaluation by the opto-electronics group for integration in the 50 000 analog links required to read out the tracker data.

To support the use of these chips in the collaborating Institutes and in test beams, the group also provided application boards, which were distributed as preliminary versions of the CMS tracker control system to more than 12 external Institutes. In the summer of 2000 these boards were used in prototypes in a test beam with a 25 ns structure.

For the readout of the CMS preshower detector, the PACE2 front-end was developed in DMILL technology in collaboration with the Institut de Physique Nucléaire, Lyon and Aurelia Microelectronics (IT), who developed some of the digital building blocks. This new version of the preshower front-end electronics is partitioned into two separate chips in order to minimize cross-talk.

A complete radiation-hard Gigabit/s dual-protocol serializer chip was designed and fabricated in the 0.25 µm technology for readout of the ALICE pixel detector. The group is collaborating with CMS in the adaptation of this ASIC for the optical readout links of the electromagnetic calorimeter, the pre-shower, and the muon RPC chambers.

Pre-production of the 16-channel LCT chip for the trigger readout of the cathode strip chambers of the CMS muon detector was launched. Measurements of the LCT chips were in conformity with specifications, and a good yield was measured on a sample of 500 chips. Also for the CMS muon drift chambers, a radiation- soft, high-resolution, time-to-digital converter was designed and fabricated in 0.25 µm technology.

Common projects. The four LHC experiments and the LHC machine will use the group’s TTCrx ASIC, developed for the common timing, trigger and control distribution system. After a successful prototype run, in

118 Experimental Physics Division which 50 chips were produced, the design of the final version of the DMILL ASIC was frozen and a preproduction batch of eight wafers was manufactured. Testing will be carried out in 2001.

For the radiation qualification of ASICs and Commercial-Off-The-Shelf (COTS) components, an agreement was reached with the Cyclotron Research Center (CRC) in Louvain-la-Neuve (B). In October the group co-ordinated the first irradiation campaign at Cyclone, in which five different LHC groups participated. Irradiation campaigns were also organized in the 300 MeV proton and 200 MeV pion beams of the Paul Scherrer Institute. In collaboration with ST Microelectronics (IT) a prototype radiation-hardened negative- voltage regulator, intended for the LHC experiments, was fabricated and tested. A final prototype is scheduled for delivery in March 2001 together with a positive-voltage version.

Product Engineering and Support Group (PES)

The Product Engineering and Support (PES) group gave support to many experiments in the research sector and to the accelerator divisions.

The Layout (LT) section produced layouts of printed circuits or hybrids for 148 customers from all over CERN. In total more than 300 new jobs were treated, plus about the same number of iterations of prototype jobs. This corresponds to an increase of some 20% with respect to 1999. Examples of high technology designs were circuits for high frequency signals and for RF applications, flexible circuits, hybrid circuits on ceramic, circuits with micro vias and filled vias for BGA applications, layouts for detectors like GEMs and with line widths below 80 µm. Great effort was invested to improve the quality of the documentation and the registration of all technical and administrative details of the jobs in a database.

The Assembly Workshop (WS) continued its support by building up crates and by mounting electronic modules. Repair and modifications of prototypes formed a substantial part of the activities. The number of projects was comparable to last year, i.e. a total of more than 1000 jobs for roughly 250 customers was treated. Twenty-five per cent of the production of boards with fine pitch components was outsourced to local industry. Tests of a new technology (hot bar soldering) were carried out in collaboration with a company in the Netherlands. This method will be used in 2001 on a larger scale for the wiring of the HARP TPC endplates. Mechanical jobs – such as front panels – are outsourced to a company in Spain. Following a call for tenders, sent to European industry, four contracts for the production and delivery of series quantities of printed circuit boards were established, which complement the production of prototype quantities at CERN. In addition, the contract S081 was modified by transforming a certain part of means-oriented activities to result-oriented tasks with detailed price lists instead of payment according to the number of hours of the personnel.

The PC and Mac Support team gave support in the domains of installation, usage and maintenance of PC and Mac hardware and software to staff and visitors of the EP division. It was, however, split off the group during Spring of 2000, to join another group in the division. Three members of the LT section also joined other groups in EP. This restructuring was done as preparation of a transfer of the two sections LT and WS from EP division to EST division, which officially took place at the end of the year.

Experimental Physics Division 119 Electronics Design Group (ED)

The mandate of the EP-ED group is to give support to both ALICE and LHCb experiments. However, the group responsibilities may also extend to support other non-LHC experiments. In 2000 the main activities of the group were focused on ALICE pixels for the ALICE ITS system, LHCb pixels for the LHCb RICH, ALICE TPC, LHCb DAQ, and LHCb VELO. As extended activity, additional support was also given, or started, for CERES, HARP, NA60, and CAST.

ALICE and LHCb Pixels. This is a common project where ALICE and LHCb experiments use a pixel detector readout chip, developed in collaboration with the MIC group. More recently NA60 has shown interest in the pixel design for their tracking telescope. The contribution of the ED group has concerned part of the design of the digital readout, the de-randomizer buffers, and the detector control system. The chip was submitted to an 0.25 µm run at the beginning of September 2000 and 12 silicon wafers arrived at mid November 2000. Tests to characterize the chip in detail continue.

A second activity for the pixels project was the development and installation of three laboratory test systems. The ALICE chip is directly wire bonded to the interface card, while the LHCb chip is encapsulated into a commercial pin grid array carrier that plugs on a socket of the interface card.

For the test of an ALICE half-stave (i.e. 10 chips interfaced onto the same pixel bus) an additional card was produced to verify the functionality of a complete ALICE structure. The behaviour of the pixel chip is checked with full automatic control of all the operating conditions. In the ALICE readout chain, the study of the pilot chip is now concluded. The readout logic has been designed in 0.25 µm. The decision to also include the detector control logic within the same chip has delayed the chip submission by two months. The pilot chip is therefore planned for foundry by the end of April 2001.

The group was responsible for preparing the specifications of the future LHCb Pixel Interface (PINT) chip, whose role is equivalent to the ALICE pilot chip. Design work is foreseen to begin in 2001.

Many improvements have been made to the study of the ALICE infrastructure. A full bus structure is now proposed. Power is provided through an additional flex copper bus connected to the MCM and to the aluminium bus. Radiation-tolerant voltage regulators provide the necessary stable and noiseless power to the couples of ladders.

The last unit in the pixel detector readout chain before the DAQ input is the router unit. It is a 9U VME motherboard with six link receiver daughter cards. These daughter cards perform zero suppression, data encoding, and event buffering and are the responsibility of CERN. The motherboard, which assemble the event fragments for the DAQ, is the responsibility of Kosice. The precise definition of this unit has started.

ALICE TPC. The front-end electronics for the ALICE TPC consists of about 570 × 103 channels. A single readout channel is made of three basic units: a charge sensitive amplifier/shaper, a 10-bit 10-MSPS low-power ADC, and an ASIC that implements tail cancellation, baseline subtraction, zero suppression and multiple- event buffering. The complete readout chain is contained in Front End Cards (FECs) attached to the detector mechanical structure.

120 Experimental Physics Division The architecture of the TPC FEC was already defined in the 1997. Some of the components and system functions were tested by the implementation of a small TPC prototype which was installed in NA49 and tested in 1998. The same electronics was used in 1999 to study and compare different technologies for TPC readout chambers. An important milestone in the design of the final system, achieved in 1999, was the development of a prototype of the digital ASIC. In the year 2000, a new design of the digital chip was completed. It incorporates eight channels and the digital filter. This new design is implemented as a 0.35 µm (triple metal) CMOS process (AMS) and has a silicon die of 40 mm2.

LHCb DAQ. The Readout Unit (RU) is a multipurpose device with application in the DAQ system, level- 1 Vertex trigger (L1-VELO) and as front-end multiplexer for the detector links. The device was designed to perform at 40 kHz sub-event building rate in the entry stage of the LHCb DAQ system. By Easter 2000, the first two 9U prototype boards were completed and tested. They performed all sub-event building functions and the link multiplexing. A final revision of the RU was started in July 2000 to achieve lower cost and enhanced performance. This latter was particularly important to deal with the high-rate level-1 trigger application.

The final RU-II modules arrived at the end of 2000. Laboratory tests in January/February 2001 confirmed the full functionality of the motherboard hardware with the new VHDL state machines. The initial commercial embedded CPU card on the RU prototype was replaced by a standard PMC mezzanine card, the Monitoring and Controlling Unit (MCU), of our own design. Two MCU cards were delivered early 2001 and are now under test on the new RU-II.

A Sub-event Transport Format (STF) pattern generator was implemented in a Slink card. Four of these cards are in use as input pattern generators on the RU-II modules. Another Slink card with 4 Glink inputs on a single card was designed. The STF was proposed to the LHCb Collaboration for transmitting data between the level-1 buffers and the DAQ. The STF was formally accepted during the LHCb workshop in May 2000.

LHCb VELO. The SCTA-128 is an analog readout chip in DMILL technology, conceived for ATLAS that has been thoroughly re-implemented with several LHCb-specific requirements. This activity, which allowed the SCTA to work in the LHCb environment, mainly concerned the readout speed improvement, the dead- timeless triggering, and the longer L0 trigger latency. The digital part of the chip was largely designed from scratch, particularly the readout sequencer, the trigger unit, and the serial configuration. The layout was submitted in December in a joint engineering run with two other projects. Since the submission, work has been focused on the preparation of the chip test set-up. The test system is based on ADC cards followed by a digital Slink transmission into a PC, using the PCI-FLIC card (see later in the NA60 Section). The chip is expected in April 2001.

CERES TPC. The readout electronics for the CERES TPC consists of 16 × 103 channels and it was originally based on seven different custom modules. This system was used to read out the detector during the years 1998–99. At the beginning of the year 2000, the collaboration asked the ED group to upgrade their electronics in order to improve the low data-taking. After detailed investigation the proposed upgrade consisted of a complete replacement of the TPC readout system.

A new system was built, based on a modified Front End Digital Card (FEDC) developed as prototype of the ALICE TPC front-end electronics in 1998. The FEDC replaced six of the seven units belonging to the chain of the original CERES readout electronics. The overall system consisted of eight VME crates, equipped

Experimental Physics Division 121 with 9U FEDC boards, controlled by a 6U VME-PCI bridge. This system ran during the beam time with an extremely high efficiency and allowed the successful collection on tape of about 45 million events.

HARP. The group contributed to the design and implementation of the full TPC detector analog and digital electronic chains. The first job consisted in participation in the construction of a small TPC prototype detector (TPCINO, 24 channels in total) used to optimize the performance for the HARP environment. This detector was equipped with CALICE2 preamplifier/shapers, the same ones used to study the NA49 TPC and readout by pico coaxial cables.

Later, a new version of the preamplifier/shaper (CALICE3) was developed, optimizing the noise and coupling efficiency to the flat cathode electrodes. Two thousand ICs were produced, along with the test unit necessary to validate their mass production.

For the test and calibration of the beam, the electronics for five proportional chambers was partially recuperated from the DELPHI HPC and checked. Two hundred cards, including a preamplifier, a comparator and an ECL driver, were constructed. So far three chambers are fully installed. Their detector control electronics is in fabrication. Finally for the HARP RPC detector, the study for a new preamplifier was accomplished. The design of a card containing eight such preamplifiers and a sum signal was concluded.

NA60. The DAQ system revision for the NA60 experiment is progressing, in view of the October 2001 scheduled run. The readout system of the NA60 muon trigger acquires data from the muon chambers and the trigger hodoscope. Rates up to 8000 triggers per SPS burst are planned and this requirement is not achievable with currently available equipment. A spill memory of at least 8 Mbyte is necessary to fulfil the needs of data buffering. For this purpose, a new general-purpose I/O card for the PCI bus (PCI-FLIC card), is being designed, allowing the interfacing of the existing dimuon spectrometer CAMAC readout system to the Local Data Concentrator computers.

CAST. This experiment plans to detect axion particles generated by the Sun by pointing one of the first prototype LHC superconducting dipoles towards the rising and setting Sun directions. The detector consists of two small wire chambers located at the two ends of the dipole magnet. The digital readout modules that the group committed to deliver will be recovered from the electronics already developed for CERES and HARP (FEDC). The experimental team will design the corresponding analog electronics. This activity has just been started and is planned to continue in the year 2001.

Experiments Operational Support Group (EOS)

Support to LEP experiments continued until the final decision of decommissioning in November. This support consisted of preventive maintenance of the safety equipment in operation in the LEP experimental areas and operation of the systems GSS (General Safety System) and SDN (gas leak and fire detection), running and maintaining at an engineering level the ALEPH and DELPHI superconducting solenoids, continued responsibility for the pool of G64 monitor and control cards used in LEP and SPS experiments (ALEPH, DELPHI).

Support to LHC experiments is increasing. LHC-oriented activities were assigned to the major part of the group: improvement of the X-ray tomograph for measurements in passive and active method of the wire

122 Experimental Physics Division positions in the ATLAS multilayer muon chambers and participation in the measurements of prototype chambers, progress of the common magnet controls project for the superconducting magnets of the ATLAS and CMS experiments aiming at harmonization of the control systems to simplify future operation.

The following activities were carried out:

– the functional description of the CMS magnet control system came to an end including process controls, magnet protections and supervision;

– the control system for the ATLAS B00 test was installed in hall 180 and put into operation;

– the first Magnet Safety System prototype including quench detection was constructed and sent to KEK for tests of the ATLAS Central Solenoid;

– the definition of the magnet control system of LHCb was assessed and included in the Magnet TDR.

Support to fixed-target experiments continued with:

1. Technical support to NA48 (slow controls hardware).

2. Participation in the CNGS project (magnetic horn and reflector construction, reconditioning of the WANF electrical circuits for double pulse operation, final installation of these facilities in situ) with the following major items in 2000:

– Collaboration meetings within the CNGS project for magnetic horn and reflector construction by LAL Orsay. Regular technology transfer meetings take place completed with extensive horn test programs in BA7.

– 1.5 million pulses fatigue test of the CNGS inner conductor prototype at nominal 150 kA current.

– Improvement studies of the cooling system.

– Construction of the 50 ms double pulse thyristor arrangement including a new recuperation scheme of reduced 6 ms duration.

– Stress and fatigue studies undertaken by LAL/Orsay and EST division (Cracow University).

– Ongoing vibration measurement programme performed with the active help of EST-SU group.

Restructuring plans of the technical support sector finally led to the merging of EOS group with EC group and others into a new TA3 group at the end of the year.

Electronics Support and Service Group (ESS)

The mandate of the ESS group is to provide services and support for electronics instrumentation used in the CERN-based experiments. Services include the Electronics Pool, a server-based embedded processors software service, and technical documentation of supported instruments. Support is available for online electronics systems controlled by embedded processors or desktop computers, front-end electronics, standard crates, high- and low-voltage power supplies, and general laboratory instrumentation.

Experimental Physics Division 123 The ESS group acts as the interface between the users and the suppliers of equipment. It is responsible for the purchase, administration, verification, and maintenance of the equipment. It evaluates new products and constructs prototypes with the help of users and outside manufacturers. The group gives both technical and administrative help and provides a documentation service.

Activities during 2000. During 2000 the ESS group continued its general support activities for the running experiments (LEP, NA45, HARP, etc.) and started a major involvement in common activities for LHC experiments. The group participated in several LHC working groups and projects and its role as a partner in the preparation of LHC experiments is increasing. The Advisory Committee for Electronics Support (ACES) advised the EP Management on the future involvement of the ESS group, based on common projects, DCS and a new support service tailored to LHC requirements.

The instrumentation section was asked to construct a prototype generic rack, using recuperated racks from LEP experiments, to test the efficiency of the cooling, to find solutions for the power supply, and to design the rack control part. Similarly, since this section invested in VME crate prototypes in the past, it was asked to continue to furnish test beams and small experiments with such crates, to start testing the possibility of operating the power supply remotely from the crate, and to have the option of water-cooled power supplies. Radiation tolerance tests continued on DC/DC and AC/DC converters in Belgium and at CERN in collaboration with experts from the LHC experiments. Universal, multichannel, power supply systems were evaluated during 2000 in collaboration with LHC experts. This work will continue in the future. Commitments to common projects, like GIF and the rack control, were made during 2000 and solid preparatory work is in progress for those challenges. Participation in ATLAS and ALICE DAQ as well as CMS test beams was also performed in 2000 and will continue in the future. Preparation for general support for the TTC, ELMB and S- Link was also undertaken.

The merging of the front-end and on-line sections into a single section (OF) permitted a faster development of common resources, such as the upgrade of test-benches from the OS9-based systems to new PC, Windows, LabView, C environment and National Instruments MXI2 interfaces to control VME and CAMAC systems. A common way of developing test software was established within the section and outside CERN with the manufacturers. New test-benches and modern software facilitated the basic work of verification of instruments as the work could be outsourced, saving precious time. Urgent requests for help from HARP and other experiments, as well as specific short-term design work, were handled primarily by this section.

The Electronics Pool section continued to provide an appreciated loan service to users during 2000. The Pool income reached a peak of 3.3 MCHF for the whole year (including the last four months of 1999). Pool investments were made for 1.6 MCHF and Pool maintenance costs amounted to 300 kCHF. Provisions for difficult years to come have been secured with the help of EP management and the Research Director. Pool investments in 2000 mainly concerned purchases of crates (6U and 9U) and front-end modules (ADCs, TDCs, etc.) in the VME standard for 50%, laboratory instrumentation (including a top performance, 1.5 GHz oscilloscope) for 40% and NIM modules for 10%.

The new database (based on BAAN4) developed in collaboration with the AS division has been operational since March 2000. It is fully integrated with CERN services like ORIAC, BHT, Foundation, etc. As a result, the invoicing procedure has become mostly automatic.

124 Experimental Physics Division With the closure of LEP, massive returns of Pool equipment are expected in the early months of 2001. The Pool therefore requires more storage space as well as an easier way to sell used equipment to outside institutes.

Experimental Physics Division 125

Information Technology Division

Overview

At the beginning of the year the Division adopted a new organizational structure in order to be better prepared for the rapidly evolving IT challenges and the decreasing manpower situation inside CERN in general and the Division in particular. The former Application Software and Database (ASD) and Information Process and Technology (IPT) Groups were merged to create two new entities, namely the Applications for Physics and Infrastructure (API) Group and the DataBase (DB) Group. The former Desktop Infrastructure and Services (DIS) and Computer Operations (CO) Groups were dissolved and a new Technical Services (TS) Group was established. Additionally all Linux/UNIX systems support was consolidated in PDP.

The Windows desktop support and the former IA Group were merged into the Internet Services (IS) Group, to provide a common base for collaborative tools and applications, as well as support of the Windows desktop at CERN.

CERN and the IT Division took a leading role in securing the EU approval and funding of the European DataGRID project, whose aim is to allow computer clusters in the LHC era to interoperate as easily as the power grids supplying the consumers of electricity. CERN will provide the overall project leadership and the co-ordination of two work packages, namely the Work Package on Data Management and the one on Fabric Management.

In the Computer Centre the harmonization of the multiple Linux clusters paid off in several ways. Using the Experimental Filter Farm (EFF) cluster, multiple experiments were able to move in to perform scalability tests and mock data challenges on hundreds of processors. Even more importantly, quick reconfigurations of these clusters allowed ALEPH and DELPHI to carry out extensive Higgs searches during the last stages of the LEP run.

A modernization of the AFS server hardware resulted in a much-improved hardware and software stability for this vital subsystem. Nevertheless, given that AFS remains a ‘niche’ product with an uncertain commercial support in the future, a study group was launched towards the end of the year to seek replacement data- management solutions for CERN and HEP.

The Division unified its problem reporting system thanks to an enhanced implementation of Remedy, one of the leading commercial products in this domain.

All PC hardware purchases were regrouped in the new TS Group inside the Division. A new tender, selecting the suppliers for 2001–2004, was completed.

Information Technology Division 127 Results from the LHC++ R&D were consolidated to create the Anaphe modular object library, which has general applicability to HEP experiments. Using Anaphe as a foundation, the first prototype of a new analysis tool, Lizard, was completed.

GEANT4 continued to be enhanced and several comparisons between simulation and experimental data were undertaken.

The HARP experiment decided to use the Objectivity database for both raw and processed data, and CMS generated multiple terabytes of Monte Carlo data, which were stored in Objectivity. In addition, the Division decided to have a close look at a new version of Oracle, which is capable of handling object-oriented data, to understand if it could be a candidate for storing LHC data.

In the area of data communications, the year could safely be defined as the transition year for moving from Megabit to Gigabit networking. The campus network moved closer to being a Gigabit-only backbone. A new 45 Mbit link to the Chicago exchange point was put in place. CERN Management decided that all communications activities should be consolidated inside IT. One unit from ST moved to IT in July and one from SL will follow early in 2001. The LHC Communication Infrastructure Project delivered several technical and organizational recommendations.

The Division continued its role of providing CERN-wide support of software for engineering design. A comprehensive licence monitoring system for engineering packages was put into production. A major effort was invested in reducing the diversion of CERN’s engineering tools.

Furthermore, the interface to link CADIM EDMS to Electronic Design Automation was released.

Overall, the demand for support of the engineering community at CERN continued to grow and put severe pressure on manpower and budget. The critical manpower situation in analogue electronic support triggered the decision to set up a CERN-wide review of computing for engineering.

The activities in the area of Controls were restructured into a total of six services and two projects, for all of which complete definitions were made available. The Division provided the leader of the interdivisional Joint Controls Project (JCOP), and participated actively in the Controls Board as well as the Field-Bus, LHC Data Interchange and SCADA working groups. IT/CO provided the chairman of the SCADA working group.

The Computing Bookshop could, once again, close the year after record sales of computer literature. The IT tutorials continued at the same brisk pace as in previous years.

The Virtual Room Videoconferencing System (VRVS) continued to be very successful. A new advanced infrastructure for Web services was deployed. The migration away from Novell Netware servers was completed, paving the way for a generalized migration of the desktop users from Windows 95 to Windows 2000 during the coming year. Computer security continued to be a major concern owing to the increase of security accidents. As a result the Division decided to enhance its efforts in this domain, despite the squeeze on human resources.

128 Information Technology Division Physics Data Processing

Integrated Services

Much time and energy was spent on the preparatory work of aligning the system configurations of the numerous individual experiment facilities, and the subsequent launching of a program to merge them into large shared facilities. LHCb and L3C were moved to form part of LXBATCH, ATLAS moved pilot nodes into this public configuration, and all other experiments agreed during the COCOTIME round to follow suit. This policy contributed to the enormous success of the shared allocatable resource ‘EFF’, used during the year by eight different experiments for periods ranging from one week to three months often in parallel with each other. Its success was also evidenced by the speed and ease with which emergency requests for vast amounts of capacity for the LEP Higgs searches were satisfied, as already mentioned. An extension of the EFF concept to include LHC and Grid functionality testing was agreed in COCOTIME and piloted in the new TESTBED facility set up in the winter.

The concept of shared facilities was only possible thanks to across-the-board uptake of PC technology. Ageing RISC equipment was replaced with PCs wherever appropriate and a proactive programme of RISC decommissioning was launched with the endorsement of FOCUS. The PLUS service emphasis was shifted firmly onto PCs running Linux by doubling the capacity of LXPLUS and LXBATCH, by withdrawing the AIX-based RSPLUS from general physics usage, and restricting the remaining DUX- and HP-based DXPLUS and HPPLUS to LEP physicists.

All this was achieved within the out-/in-sourcing IT model, by supervising the increased delegation of the low-level system administration to SERCo. The responsibility of installation and management scripts of most services was transferred from CERN to SERCo over the course of the year, in order to stimulate the increased participation in the problem analysis and resolution through ownership.

Other Computer-Centre-wide services enjoyed continuous expansion throughout the year. The DNS sub- domain management of plus.cern.ch, wgs.cern.ch, mailbox.cern.ch and Web.cern.ch maintained its high reliability during the migration onto PC servers. The Legato back-up service also grew to be relied upon by many more IT groups.

Other achievements included the installation and management of the computing facilities for the CERN School of Computing, and the continued developments of Linux code for the IA-64 architecture within the ‘TRILLIAN’ project in collaboration with industry.

Finally the revamp of the alarm and monitoring infrastructure continued slowly within the Performance and Exception Monitoring (PEM) project. After the software analysis phase, three prototype modules were implemented in Java. The software was extensible in order for arbitrary application-level events to be defined. All prototypes were made operative and scalability tests were initiated.

Information Technology Division 129 Data Management

The AFS services were modernized and homogenized, replacing some fifteen old machines having unreliable disks with six modern servers equipped with a standard RAID disk configuration. This enabled IT to migrate to the latest version of AFS in the middle of the year and the AFS services were far more stable and reliable as a result.

Two new types of tape drive, STK 9840 and IBM 3590E, both linear technology, were successfully put into production as the first steps in an ongoing programme to phase out the STK Redwood helical-scan tape drives. All tape drives were connected to cheap Linux PCs so that server cost was no longer a factor in deploying tape services. Two new robotic tape silos were put into production and an average of 15 000 tape mounts per week was performed. Evaluation of two newly announced tape-drive products and media, STK 9940 and IBM Linear Tape Open, began in the autumn.

Integration of a satisfactory PC-based EIDE disk server using standard components was completed. This enabled vendors to provide the specified configuration at prices significantly lower than traditional SCSI disk servers with equivalent functionality and performance. Several such systems were deployed and became the model for all future purchases.

The first phase of the CERN Advanced STORage manager (CASTOR) was completed early in the year and controlled deployment started. The SHIFT software it is replacing was frozen and after early tuning and debugging full-scale deployment of CASTOR began. The requirements process for the second phase of CASTOR, targeted at the future LHC experiments, also started.

Services of managed storage using the commercial HPSS software continued at a steady level during the year, successfully managing individual user large files and test-beam files totalling about 38 Tbyte volume in half a million files. This function will be progressively taken over by the CASTOR system.

Open Systems Environment

Almost all improvements of Central Batch Services were due to the move to commodity software and hardware and Linux became the mainstream HEP operating system environment. The following trends were reinforced:

– A great part of the investments for scientific computing went into Linux PCs with different kinds of usage: interactive, batch, desktop, and even portables.

– The number of Solaris systems on site remained more or less constant but most experiments expressed some need for Sparc and Solaris as a second or ‘verification’ platform.

– The environments based on all the other commercial UNIX variants were frozen and their usage started to decrease.

The Linux 2000 project delivered solid improvements in the managed Linux environments like installation management, software distribution, kernel testing and debugging, and specific portable environments. Desktop environments were studied and a proposition for standard GNOME installation was pursued.

130 Information Technology Division Solaris 7 was certified for continued physics use, especially in the context of the verification platform already mentioned. AIX was definitely frozen and in addition the support for DEC UNIX and HP-UX was greatly reduced.

Technology for Experiments

Services

During the year the CDR service managed the data recording for the following experiments: NA48, NA45, L3C, test beams of the LHC experiments, as well as the production data from the CMS ORCA productions. The total data volume recorded exceeded 100 Tbyte and the peak data rate attained 40 Mbyte/s for NA48.

Dedicated Objectivity Lock Servers provided the production Objectivity services for large collaborations: ATLAS, CMS, COMPASS, and NA45. IT was also involved in the support of the CMS CRISTAL Objectivity database using Windows NT server and Dothill RAID hardware. During the year, the CHORUS experiment began an emulsion data analysis and an Objectivity federation of 80 Gbyte was populated. The CHORUS database is hosted on Hitachi RAID hardware.

The HIPPI network completed its final year of service, and will be shut down in early 2001.

Future Experiment Requirements

The COMPASS experiment successfully tested its Central Data Recording and online processing scheme in its first year of data-taking. With more than 100 dual-processor PCs and 20 PC disk servers, sustained data rates of 35 Mbyte/s (peak 50 Mbyte/s) were achieved.

Another very important step this year was the ALICE Mock Data Challenge II. Despite a very challenging hardware and software set-up and the corresponding number of technical problems, peak data rates of 100 Mbyte/s from the DATE data acquisition set-up into the CASTOR HSM system were reached.

The Compass Computing Farm was set up to a configuration of about 25% of the CPU capacity and almost a 100% of I/O capacity. Three terabytes of disks were attached. The ten weeks of running allowed debugging and better understanding of many aspects, from the operation to the data. CASTOR itself was used for the first time in production with HSM functionality. Two more weeks of data-taking were performed in November. About 3 Tbyte of real data were put on tape, and the measurements done with real data confirmed the previous experience with mock data. The status of the project was illustrated at CHEP-2000 and at ACAT-2000 and corresponding written contributions were sent for publication in the conference proceedings.

Concerning Storage Area Networks, the GFS evaluation was completed and a report written, concluding that a production GFS service was not feasible owing to a lack of software maturity and performance.

A price enquiry was made for high-quality Fibre Channel attached RAID disk capacity to support both high-performance and high-reliability applications. The winner was EMC-Clariion.

Information Technology Division 131 Data Grid Project

Quite a large amount of preliminary planning and design work was performed for the Data Management Work Package by IT staff, in addition to work on the installation of the Globus TESTBED at CERN. Furthermore, a Kerberos V5 server was installed and all the software infrastructure needed to generate AFS tokens from X509 certificates was put in place (including heavy debugging of existing code).

Other activities

In September, the second demonstration of High Performance Networking Technology was organized at CERN, including IP and SCSI/ST running over GSN, Fibre Channel and Gigabit Ethernet. The development of a 2.5 Gbit/s OC-48c interface to the Genroco ST/SCSI Bridge was completed and demonstrated. This was carried out as a joint project between CERN and Genroco.

Technical Services

Computing Hardware

The purchase and resale arrangements for PC hardware were grouped into a single section in the new TS Group at the beginning of the year. This regrouping brought together responsibility for standard systems (desktop and portable PCs and monitors) and for specialist hardware such as that for physics computing farms, e.g. PC-based CPU and disk servers.

The service delivered over 1300 desktop PCs and 150 portables during the year. Compared to 1999, this represents an increase in desktop systems but a slight drop for portables. Overall, including display monitors, CPU servers and other items, IT handled the purchase and resale of computing hardware worth more than 6MCHF.

A major activity during the year was the selection of hardware suppliers for 2001–2004. The aim of the tender process was to ensure flexibility and competition amongst suppliers in order to ensure the best purchase prices for CERN whilst maintaining, and even increasing, PC standardization in order to reduce the total cost of ownership for PC hardware. This difficult process was finally completed towards the end of the year and will come into operation at the beginning of 2001 as planned.

Although standardization is essential to reduce total cost of ownership, one size does not fit all and so additional standard systems were introduced during the year to meet specialist needs. In addition to dual- processor CPU servers (a standard for physics computing users), IT selected a lightweight portable for frequent travellers, and the Division is standardizing a PC configuration to support 3-D intensive engineering applications.

Continuing the standardization theme, the Division worked actively to harmonize the purchase procedures and tools for all commodity-computing hardware (including printers and Macintoshes), increasing the internal

132 Information Technology Division integration and fluidity of the administration. IT hopes to build on this harmonization to improve the purchase process for end-users during 2001.

Computer Centre Co-ordination and Management

Computer Centre Operation

The advent of PC-based computing has led to a significant increase in the number of systems in the Computer Centre. Faced with this increase the Division introduced a service to ensure the orderly installation of systems in the machine room and, perhaps more importantly, the orderly removal of obsolete systems and cabling! This installation service will become more important over the next few years as IT has to fit an ever larger number of systems into the available space and ensure that they can be found should there be any problems.

In spite of increased automation, the large number of systems in the Computer Centre meant that there was still a need for a console operator team to respond to alarms and restore service quickly in the event of problems. As the existing contract with a service company for operator and tape-handling services will expire shortly after 2000, future operator requirements were reviewed during the year and a Market Survey was issued as the first step in a tendering process to be completed next year.

Computer Centre Infrastructure

As noted in last year’s annual report, the automation and centralization of tape facilities has led to a concentration of data in the Computer Centre and a physically remote location is needed to reduce the risk of data loss. A potential remote site was located and after much work with EP and ST Divisions, a new building, B613, was approved in the autumn. Construction of this new building, located about 100 m from the Computer Centre, is scheduled to start in February 2001.

An investigation into how CERN’s Computer Centre can be adapted to meet the major infrastructure requirements of the LHC computing farms was started in 1999 and this continued, with close collaboration from ST Division, during the year. In addition to examining our existing infrastructure, the arrangements at Computer Centres outside CERN were reviewed and a Data Centre consultancy conducted an initial feasibility study for the refurbishment and upgrade of B513. By the end of the year it was clear that, although much investment is needed, the thirty-year old Computer Centre could be upgraded to meet LHC requirements.

The broad outlines of possible upgrade scenarios that were sketched during the year must then be developed into a detailed plan during 2001 for execution in 2002–2004, such that the Computer Centre will be ready for the expected build-up of computing hardware prior to the start-up of LHC in 2005.

Information Technology Division 133 Industrial Contracts and Software Licensing

Desktop Contract

The Desktop Contract, started in 1999, continued this year and increased in volume, not only the number of cases dealt with (more than 32 000 over the 12 months), but also in the number of areas of CERN covered.

A number of CERN divisions and groups joined the contract to obtain localized support of their desktop systems or applications. In addition, a number of CERN experiments subscribed to the contract to obtain support for their experimental set-ups. By year-end, as well as the general desktop support, Helpdesk operations and printing support, IT was supporting 17 distinct divisions and groups and 5 experiments. Accordingly, the contract will be considered as a Distributed Computing Support Contract.

Contract Assistance

Drawing on the experience gained with the Distributed Computing Support Contract, the TS Group in IT offered help and advice to other groups for outsourcing. As an example, the PDP Group took advantage of this in the context of the System Administration Contract.

Software Licensing

During the year, the contracts with the various UNIX RISC vendors were reviewed. After consultations with the appropriate users inside the Division and across CERN, the software support contract with HP was stopped mid-year and that with IBM at the end of the year.

Other software contract work included the renewal of CERN’s Microsoft Educational contract and the acquisition of a number of products, mainly for use on NICE or for the forthcoming Windows 2000 rollout.

The Flexlm licence management service was reviewed also and the three nodes, which form a redundant ‘2 out of 3’ server cluster were upgraded to more powerful models. In addition, the software configuration was put under examination with a view to more automation and better recovery from errors, although this service had proved in the past to be remarkably stable.

Interfaces and Remedy

Problem and Call Management

The Remedy service was expanded to offer facilities to new groups and experiments through the two main applications, PRMS (a general tracking problem system) and ITCM (a specialized contract management system). The entire service was judged impressive by an outside consultant following a review in May that also gave much valuable input to our development plans.

134 Information Technology Division Following modification at the beginning of the year, in order to support multiple domains and provide independent workspaces for new groups or experiments joining the application, PRMS was, at the recommendation of the consultant, completely separated from the standard Helpdesk application provided by Remedy. This separation was judged an essential step to ease both maintenance and future developments, such as the integration of the User Support Group requirements that took place in the autumn. Following this, attention switched to improving the management tools in order to delegate administration work to the many different groups using the PRMS application—a feature missing from the basic product.

The ITCM application was modified over the summer to support the new Network Management contract. Many new features were added, such as Domain Management, Escalations and Group Assignments that were also of benefit for the management of the PDP Systems Management contract.

More generally, both applications benefited from improvements in the handling of electronic mails to support lines, the introduction of an improved Web interface and the use of Seagate’s Crystal Reports product to create regular reports and thus exploit better the data recorded by the Remedy applications.

Finally, and again following the consultant’s recommendations, a dedicated application was designed at the end of the year to track problems and enhancement requests for the Remedy service. In 2001 the Remedy support team will also be Remedy users!

Operator Interfaces

The Performance and Exception Monitoring (PEM) project, already mentioned, was designed not only to improve the quality of system monitoring, but also to update the way in which alarms are monitored and managed by the console operators.

Additionally, continued support for various commercial or homemade applications, including ADSM, SURE, Logger and the TVScreen, was provided.

Macintosh Support

In the area of Macintosh Support IT continued to provide central sales, support, repairs and maintenance for Apple hardware, software products and peripherals during the year. Over 160 Macintosh systems were installed for CERN users and, towards the end of the year, Macintosh purchase and resale arrangements were integrated with those used for PCs. As a further step to integration, the Mac Support Web pages were moved to the divisional Web services, and there was continued support of the hardware behind the operating systems and applications installation service as well as a back-up service for Mac users.

Continuing the focus on newer Macintosh systems (following the phase out of 68000-based Macs last year), support for LocalTalk was discontinued during the year and IT prepared the migration away from AppleTalk to IP protocols for printing.

Information Technology Division 135 Print Services

The trend towards colour printing and locally attached printers continued. More than 300 printers were installed, of which 65% were colour (up from 55% in 1999) and 45% locally installed (40% in 1999). Fortunately, the new PC-based print servers coped well with the new load and the old RISC-based print server was not missed.

A key focus in the area of Print Services during the year was the reorganization of the workload to streamline routine tasks. The first step was to integrate the handling of user requests and telephone calls with the Helpdesk service and to use Remedy for report handling. Then, towards the end of the year, the arrangements for printer purchase and resale were merged with those for PC hardware and agreement was reached with SPL Division for the transfer of consumable purchase and resale to the Stores service.

These changes should allow the Print Services to concentrate on the technical aspects of the service and, following a review of problem areas in the autumn, a plan to further improve the Print Services was presented at a Desktop Forum meeting in November.

Finally, the HEPiX community expressed interest in the CERN print server configuration and IT believes that this will lead to collaboration with another HEP laboratory for development work in 2001.

VXCERN

Higgs boson hunters were not the only ones with an interest in keeping LEP running in 2001! It was agreed in 1998 that the VXCERN service would close with the end of LEP data-taking and VMS lovers were hoping for a stay of execution. As we all know, LEP was turned off for ever in November and so preparations were made in December to shut down the faithful VXCERN service — first introduced in 1984 and thus, at over 16 years old, one of the longest running CERN computing services.

Other Activities

Following the October meeting of HEPiX, a new emphasis was placed on seeking more active collaborations with other laboratories, especially but not limited to the area of computer centre farms. Some initial contacts were made and followed up.

Applications for Physics and Infrastructure

Introduction

As a new group in IT, the main task of the API Group is the development and maintenance of application software components to be used by the physics experiments as well as providing support for the software process. The developments are done in object-oriented technology; legacy software written in procedural languages, such as FORTRAN will be maintained for a limited period of time but with decreasing resources.

136 Information Technology Division Analysis Tools and Libraries

Program Library

The 2000 release of the CERN Program Library was well received by our users. The current planning foresees a final CERN Program Library Release by 2002, after which the package will be put in the public domain, and all maintenance by CERN/IT will cease after 2003.

Data Analysis

Underlining the fact that the software developed in IT/API is not limited to the LHC experiments, the LHC++ project was renamed Anaphe.

The main activity concentrated on a new, command-line driven, interactive data analysis tool (Lizard). After the initial design phase a first prototype was released in the spring. A second iteration of the design focused on decoupling the various categories and the creation of Abstract Interfaces for each category. These interfaces were in turn implemented in C++ in the form of wrappers/adapters to the existing libraries of the Anaphe project.

A functional prototype of this analysis tool (Lizard) was delivered in the autumn, preparing the ground for a full release planned for spring 2001. This functional prototype was successfully used at the CERN School of Computing.

In parallel, contributions were made to the evolution and further development of the CLHEP class libraries and the set of Abstract Interfaces from the AIDA Group. The use of the AIDA interfaces is spreading in other products such as the Gaudi/Athena framework (in use by ATLAS, LHCb and HARP), the IGUANA and CARF frameworks (CMS), and the new GEANT4 analysis package. In the context of the last of these, the predicted interoperability between independent analysis tools (JAS, Lizard and OpenScientist) — all based on AIDA interfaces — was successfully demonstrated.

The maintenance work for the commercial libraries used in the Anaphe project could be reduced in the second half of the year as the number of supported platforms was smaller than in previous years. The continuing observation of the market, however, led to the adoption of a new class library for 2-D graphics (Qt).

WIRED

WIRED (World-Wide Web Interactive Remote Event Display) is a framework (written in Java) to construct HEP event displays that can be used remotely across the network. WIRED was integrated with JAS (Java Analysis Studio) and adopted the HepRep standard to interface with experiment data in both Java and C++. PostScript and SVG (Scalable Vector Graphics) output drivers were added to WIRED to allow for proper inclusion of WIRED plots into electronic documents.

Information Technology Division 137 Simulation

As far as simulation was concerned, IT focused mainly on support, development and maintenance of GEANT4 (written in C++ and based on an object-oriented design) as part of the GEANT4 Collaboration, while contributing to the maintenance of GEANT3.21 (written in FORTRAN).

This year was the second year of the production service of the GEANT4 simulation toolkit. There was a heavy involvement in the coordination of the project; in particular by providing the chairperson of the GEANT4 Technical Steering Board, in which other IT members also participated actively. Moreover, IT was responsible for two working groups: Geometry & Transportation and Software Management.

The Division fully contributed to all milestones of the GEANT4 Collaboration for the year, in particular to projects comparing simulated data with experimental measurements, the development of training kits and software process assessment and improvement.

A new policy of releasing monthly reference tags to collaboration institutions was agreed and put in place. These tags were development releases that included all tested fixes and all tested new developments.

Public releases included a minor release (GEANT4 1.1) in March, and major releases in June (GEANT4 2.0) and December (GEANT4 3.0), all made on schedule, and intermediate patches issued for important fixes.

These releases added the ability to use ISO C++ compilers, while retaining the ability to compile with traditional compilers. They included new physics processes and models, such as improved hadronic physics support, including a design iteration of the pre-equilibrium model, improvements in the implementation of electromagnetic processes, e.g. for Bremsstrahlung a new cross-section and energy-loss parametrization was introduced. At the same time, a number of comparisons between simulation and experiment were performed, in particular for the geometry, and for the electromagnetic and hadronic physics.

IT contributed to the evolution and development of several categories (geometry, software management and electromagnetic and hadronic physics) and continued to play the leading role in the system integration tests of the toolkit and the releases. Tools for the automation of the tracking of tags and for the generation of tag-sets for system testing were developed and put into production.

The continued maintenance of GEANT3.21 remained a background activity. No new version of GEANT3.21 was released.

Software Process Support and Documentation Systems

The Software Development Tools service (SDT) continued selecting, evaluating, installing and maintaining a dozen commercially available tools for several UNIX hardware platforms.

The DocSys service provided the ongoing FrameMaker and Template support. Primary usage of Adobe FrameMaker is on UNIX platforms (more than 1000 users) and on NICE or standalone PCs (with a total of about 500 users). A new generic template package, the Software Documentation Layout Templates (SDLT)

138 Information Technology Division for the production of software documentation, was introduced in January. A second release in July implemented a number of enhancements requested by the users.

XML (Extensible Markup Language) became important as a lingua franca for storing and transmitting electronic documents and played an ever-growing role in many applications used in the CERN environment. The IT/API Group was active in the Esprit TIPS (Tools for Innovative Publishing in Science) project, whose aim is to improve information production and dissemination. CERN contributed primarily in the area of building a coherent set of tools for, on the one hand, the production of XML starting from the different document formats in use in HEP, and, on the other hand, the generation of multiple output representations (HTML, Word, LaTeX, FrameMaker) starting from the source files stored in the XML repository.

Contribution to the CEDAR Project

An Import/Export system based on a neutral XML format was developed in close collaboration with the users. This was used for the creation of breakdown structures and massive check-in of files for ALICE, TIS, CMS, SL and ATLAS. Special applications were developed for the LHC. This work will form a basis for the specification of a more powerful and robust version of the Import/Export software that continues to be under development.

Migration from legacy data repositories to CADIM was completed for TIS and ALICE. These applications demonstrated the benefit of the XML approach.

Several new projects were launched such as the Import/Export with MP5, combined use of EDMS and LIGHT, and archiving for the Design Office.

Collaboration with COMPASS

The collaboration with the off-line groups of the COMPASS experiment continued to provide software technical co-ordination. At the project level IT offered assistance in organizing the project, its repository and infrastructure, defining and implementing documentation standards and templates, tracking progress and milestones.

The participation in the COMPASS off-line team in the development of the reconstruction and analysis framework helped in defining the software architecture, coached people to object-oriented design and development, and helped introduce software engineering and documentation tools and methodologies.

Databases

Object Database Support

CERN continued to deploy Objectivity/DB as the Object Database of choice, following an extensive evaluation by the RD45 Collaboration. This year, as in previous years, a series of meetings was held with

Information Technology Division 139 Objectivity, Inc. to agree on a timetable for addressing CERN’s main short-, medium- and long-term requirements. During the course of the year, all of the short- and medium-term issues were resolved, and production versions of the corresponding software were received and installed at CERN. The primary long- term issue — that of Very Large Database (VLDB) support — continues to be discussed together with Objectivity and SLAC, and a stop-gap solution, capable of meeting BaBar’s immediate needs, is expected to be delivered during the course of 2001.

CMS continued to make extensive use of Objectivity/DB, relying on support for production services for a series of multi-terabyte Monte Carlo production runs both at CERN and also distributed across a number of remote sites. The HARP experiment adopted Objectivity/DB for its storage of raw and processed data whilst other collaborations, such as CHORUS and COMPASS, continued and expanded their usage of the system. The existing mass-storage interface was ported from the commercial HPSS product to the CERN-developed system CASTOR. A new abstract interface to the conditions database was agreed with the experiments, paving the way for implementations on other systems, such as Oracle, should a migration ever be required.

Relational Database Support

CERN continued to support Oracle as the relational database management system of choice. This system is widely used across the laboratory for a large spectrum of activities, ranging from accelerator and physics- related applications to administrative tasks. In common with the Division’s policy of reducing the number of supported platforms, several database servers were migrated to Sun systems during the year. With the current exception of the database for CASTOR, which runs on Intel/Linux, all of the main database servers were migrated to Sun systems.

At the annual Oracle conference in the USA, a new release of the database was announced. Along with many other enhancements, such as in the area of XML, server side Java, distributed database management, etc., this new release greatly enhances Oracle’s support for handling data created according to object-oriented data models and comes with a new C++ binding.

In order to understand whether Oracle could eventually be used to handle LHC event data, a series of meetings was held with Oracle experts at CERN and at Oracle’s headquarters in the USA. These meetings gave a valuable insight into Oracle’s technology for handling VLDBs and object data, and Oracle appears eager to learn from CERN’s experience in this domain.

Use of Oracle by the physics community increased significantly, in particular for handling physics data, rather than merely metadata and detector component details. Tests were made by the AMS experiment for handling both raw and tag (‘Ntuple-like’) data. In the latter case significant performance improvements — up to a factor of 100 — were seen over traditional HEP techniques, such as PAW.

140 Information Technology Division Communications Systems

Overview

The traditional Communications Systems activities made major progress during the year, which could be defined as the transition year from Megabit to Gigabit networking.

For the External Network activity the major milestones were the delivery of 45 Mbit connectivity to the Chicago STARTAP, the full re-engineering of the CIXP infrastructure to Gigabit together with further extension to Geneva city centre, and the connectivity between the external network and campus networks.

The Campus Network achieved its ambitious deployment and consolidation goals of the Gigabit backbone while preparing actively the next step, namely a Gigabit-only backbone with multicast and Quality-of-Service (QoS) facilities enabled. The appropriate networking infrastructure was installed and put into operation to satisfy the various requirements for physics.

The Network Service and Operation successfully introduced a new Industrial Services contract with an external company during a smooth transition period.

Indeed, the major event during the year was the strategic consolidation process, which even accelerated during the second half of the year. Thanks to the good user reception of the services delivered by IT, as well as the continued progress of the networking industry, the management of the Technical Sector and the LHC project decided to consolidate all the communication activities in IT. The Accelerator Sector management approved this decision. As a practical result, the ST/EL/TL section joined IT/CS in July. The SL/CO/NM section will follow in January 2001. The clear goal, which led to these decisions, is the implementation of a unique IP/Ethernet communication infrastructure for voice, video, and data.

LHC Communication Infrastructure Project

The LHC Communication Infrastructure Working Group (CIWG) was established in May 1999 with members from the accelerator sector, the LHC physics experiments, the general communication services, the technical services and other LHC working groups. It spent a year collecting user requirements and at the same time explored and evaluated possible solutions appropriate to the LHC. A number of technical recommendations were agreed, and areas where more work is required were identified. The working group also put forward proposals for organizational changes needed to allow the design project to continue and to prepare for the installation and commissioning phase of the LHC communication infrastructure.

The recommendations of the CIWG were presented to the LHC Technical Committee for approval. The organizational changes were completed by the end of the year.

Consequently, the Communication Infrastructure project (ComIn) was created in the Division and several internal working groups were established with the goal to propose implementation plans by mid-2001.

Information Technology Division 141 Telecommunications

The section responsible for ‘telecommunications’ at CERN was transferred to IT in July, becoming the IT/ CS/TEL section. Its mandate covers:

– the CERN internal telephone system and its connections to the Swiss and French public telephone networks,

– the GSM mobile telephone system,

– radio and intercom systems,

– Video transmission and distribution around the CERN sites.

The transfer of this activity to IT was made in recognition of the increasing integration of data, voice, and video communications services. In preparation for this, preliminary tests were made of the transmission of video and voice over the general-purpose data network, using commercially available equipment. The results of the tests were encouraging.

The main responsibility continued to be support and maintenance. Preparations were made for the LEP dismantling, in particular to enable minimal communications facilities to be maintained during the dismantling period.

Pilot tests were undertaken of the use of different network service providers for CERN’s outgoing telephony services. This was as a result of the liberalization of the telecommunications market. The tests were positive, with few technical problems. Transparency was maintained for the user community. In 2001 the Division plans to present a proposal to the CERN Finance Committee.

Wide Area Networking

Following the call for tender for transatlantic connectivity won by KPNQwest at the end of 1999, a new 45 Mbps circuit to Chicago was successfully delivered in late March. The contract also foresaw an upgrade to 155 Mbps at no extra charge from December, but for logistics reasons the upgrade will only be performed in early January 2001.

Following the change of Telecom Operator, CERN’s Internet Point of Presence in Chicago had to be relocated to KPNQwest premises, where direct connection to the National Science Foundation (NSF) funded international ‘peering point’ STARTAP allowed numerous ‘peerings’ with other networks. Direct peering with ESnet (Energy Science network) at 155 Mbps could also be established in Chicago.

The CERN Internet eXchange Point (CIXP) continued to grow in a healthy manner both in terms of Telecom Operators presence (12) and Internet Service Providers (35). The principle of distributing the CIXP to other neutral locations inside the Geneva area was agreed and a first connection with the Telehouse premises was made using two pairs of dark fibres with Gigabit Ethernet connections.

142 Information Technology Division New fibre-optic cables were also installed, thus providing a strong foundation for next generation networks. With almost 1000 strands of single-mode fibres physically reaching the Computer Centre, there is enormous bandwidth at hand, although still at relatively high cost despite the rapidly declining prices.

Apart from the delivery of a pilot 2.5 Gbps link provided by SWITCH, the Swiss National Research network, between CERN & ETH Zurich, and a new 34 Mbps link to IN2P3 in Lyon, there was no fundamental change to CERN’s European connectivity. However, major upgrades are expected in mid-2001 with the replacement of the TEN-155 backbone by Gigabit European Academic NeTwork (GEANT), which will provide a 2.5 Gbps backbone.

In order to cater for the increased bandwidth, the interconnection between the campus and external networks had to be completely re-engineered.

Advanced WAN Applications and Tools

Continued improvements of the Internet traffic monitoring and reporting tools were achieved. During the year IT had three Internet monitoring probes in operation (RIPE, Surveyor & NIMI). The Division continued to take part in the PINGer monitoring project led by SLAC and provided real-time flow statistics.

Through its participation in TF-TANT, a European task force led by TERENA & DANTE to explore advanced networking technologies, CERN actively participated in projects on Quality of Service (QoS), MPLS based Virtual Private Networks and IPv6, the next generation IP protocol.

IP telephony products from Cisco, Nortel, and Alcatel were evaluated. All three were tested in view of integration with the existing Alcatel telephone exchange. It became clear that a completely seamless integration was not straightforward and investigations are still ongoing. Conclusions and practical recommendations are expected in 2001.

A Windows-based ACB Pilot service was introduced, offering 56 kbps and ISDN connectivity, as well as 0800-number access for dial-in only. At the end of the year the service served about 150 users and delivered over 1000 connection hours per month. Stability problems persisted, however, and further solutions were identified. In order to assess the feasibility of outsourcing part or all of the ACB services, a prototype ‘call-in’ service with Swisscom was started. The preparation of a final plan for opening a service during the first quarter of 2001 continued.

Campus Networking

The design of the new Gigabit backbone was finalized together with a proposal for backbone redundancy and enhanced connectivity between the external and campus networks.

Continuous surveying of the new products from industry, accompanied by intensive testing, demonstrated that the Ethernet hierarchy from 10 Mbit to 10 Gbit will be able to provide the adequate infrastructure for combining all the communication requirements foreseen for the LHC era.

Information Technology Division 143 The approved Gigabit Ethernet backbone deployment was actively pursued with more than 30 Gigabit routers installed mostly in the Computer Centre, physics buildings and experimental halls.

A proposal for phasing out of old FDDI backbone by deploying Gigabit infrastructure was accepted. A call for tender was done in order to face the need for more Gigabit devices.

The requirements for physics computing farms in the Computer Centre continued to grow throughout the year. This led to a very sizeable extension of the Gigabit/fast-Ethernet infrastructure often with very short implementation delay, but thanks to good collaboration between groups inside IT, the Division was able to satisfy the demand as foreseen.

The Central TCP/IP name service, Time service and DHCP service passed the Y2K issue without any problem and ran smoothly during the year.

Network Management and Operations

The main issue during the year was the new outsourced contract for first-line network services. These services, which used to be resource-oriented, were replaced by a result-oriented contract with a new contractor taking over the services on 1 April. This major change implied a lot of work, both on consolidating the procedures and implementing the software tools (including Remedy) for monitoring the SLA. During the last quarter of the year, a steady state was reached, making the network users satisfied with the services.

The Y2K compliance tests raised a number of concerns, mostly around the database issue. After an uneasy fire-fighting period, the situation stabilized, but it had demonstrated that the database environment had to be reviewed. An extensive analysis was initiated and IT expects practical implementation to be achieved in 2001.

The cable management package Mountain Top survived the Y2K compliance tests with some difficulties. As this package, running on HP-UX, was unsupported, it was decided to move to a new PC/Windows 2000 package from industry. This decision took into consideration potential consolidation savings, as the new package was already used for the fixed telephony infrastructure.

Communications Infrastructure

The conversion of small buildings and barracks to structured cabling continued. Eleven new star points were installed and more than 1100 new network outlets were made available. The progress of the structured cabling activity can be summarized by saying that all the North Area of the Meyrin site is completely on structured cabling as of this year. The programme for 2001 is to finalize the structured cabling programme on the South Area of the Meyrin site.

The wireless LAN technology was thoroughly evaluated and one reached a stage where IT expects to use this technology in a pilot programme next year. The plan is to use this technology for a number of remaining structured cabling exceptions.

144 Information Technology Division The work on fibre infrastructure for the campus network progressed according to plan. The new star points were interconnected by fibre as a replacement for the old coaxial network extension.

The streamlining and routing of the coaxial infrastructure were actively continued, but consumed much more resources than expected, in part because this activity is very dependent on the deployment of the structured cabling. By the end of the year, the number of users remaining on the old coaxial infrastructure is estimated to be below 200. IT expects this work to be completed by 2001.

User Support

Support Front-Line Activities

The Computing Helpdesk operated throughout the year at high intensity, with over 600 requests for interventions processed every week. One notable improvement in the quality of the responses provided by Helpdesk staff (outsourcing contract) took place when the Contract Managers accepted the Division’s plea to have staff dedicated to this activity rather than time-sharing among several individuals.

Problem Management Strategy

During the year the Helpdesk phased out the initial problem-solving interface, in favour of the one provided by the internal Remedy Support team in the Division. The interface served its purpose well by allowing the Division to act upon the user issues escalated by the Helpdesk since the very beginning of the contract.

User Documentation and Bookshop

Three Computer Newsletters were published. The Computing Bookshop again saw record annual sales, with some 20 new titles incorporated in its catalogue. Books were sold to an approximate value of 250 kCHF.

IT Training Tutorials

The tutorial activity accounted for 43 tutorials run during the year (11 of them imparted on location at DESY), which were attended by some 2100 users. The most attended single event was the Java series (a repeat of the experience in 1999).

Information Technology Division 145 Computing for Engineers

Digital and Analog Electronics CAE/CAD Support

At the end of the year the tool cluster for computer-aided electronic engineering (‘Electronic CAE cluster’) had some 400 registered users for whom IT provided support, ranging from hardware and software installation to library development. About half of them were from CERN, the other half from collaborating institutes. On the managerial side, ELEC continued its successful work. After some negotiations, one tool vendor gave CERN permission to license the tool through Europractice, resulting in savings of some 80 kCHF per year. The collaboration with the digital electronics CAE user group continued in a very successful way. On the technical side, the bulk of the work continued to be the day-to-day support activity. Demand increased, owing to more and more designs being carried out by visitors and people on short-term contracts, and to the ever- increasing complexity of designs. A major achievement was the introduction of the interface between Cadence and EDMS. This allowed designers to archive and retrieve electronics designs from EDMS. Of particular interest was the possibility to access files, e.g. schematics, via the Web. The result was presented at two conferences and representatives from industry considered this technique of linking commercial CAE tools via a commercial (but customized) interface to a ‘corporate-wide’ product-data management system as a breakthrough. Using EDMS for electronics designs is an integral part of a lightweight quality procedure, as proposed by the digital electronics CAE user group and endorsed by ELEC and the technical director. In collaboration with EP/ESS, users, and ELEC, a new tool (JTAG boundary scan) was introduced to test the connectivity of electronics boards and to program in situ programmable devices. The upgrading of the user CAE environment continued. This concerned the upgrading of user workstations (as requested by the users), operating system and CAE-tool upgrades, and improving user network access (from 10 Mbit shared to individual 100 Mbit). To promote high-level system, design methodology, a joint project to model and to simulate the ALICE data-acquisition system was set up with ALICE. The result achieved was a better understanding of the functioning of the proposed system and its parameters and their sensitivities under maximum throughput conditions. In view of future outsourcing, library development for printed-circuit-board footprint symbols was transferred to the Division. Training for VHDL for synthesis was organized. In addition, ‘hands-on’ training was given to newcomers to get them up to speed quickly. In the electronics CAE tools industry demand for high-end products under Windows 2000 appeared to have waned but the push continued for tools to be made available under Linux.

Demand for analog electronics engineering support increased steadily over the year. Because of the complexity of the analog electronics simulation tools, the availability of a centre of excellence to help users with their problems proved indispensable. This was confirmed by the strong reaction of the ELEC user community representatives to the threat of reducing engineering support due to the severe staffing problems in this area. It is hoped that the announced review of computing support for engineering will support the users’ request to solve this problem. During the year, there was again extensive collaboration with the LHC experiments and the Division presented two very positively received papers at LEB2000 in Cracow. The Maxwell/HFSS tool continued to be used for CLIC. SpecctraQuest tools for Signal Integrity (SI) studies were in steady use by both the accelerator sector and experiments (ALICE, ATLAS). Much work was done in characterizing ASICS for use in SI studies and a large effort was made to document this and other topics on revised Web pages. Simplorer, a recently introduced tool for power electronics simulations, continued to be in

146 Information Technology Division regular use and provided the possibility of reducing the number of expensive SABER licences. The Division also initiated formal Matlab support.

Mechanical Engineering and Related Fields

All CAD servers and associated EUCLID workstations were upgraded to Tru*64 v4.0f. The important servers for EUCLID and EDMS were made to run in failsafe mode using commercial fail-over software. This resulted in a significant improvement in fault tolerance and availability for the underlying services. In addition a locally written alarm system was installed in these servers with resulting improvements in reliability via automatic error correction mechanisms. At year’s end a new set of EUCLID server hardware was ordered to cope with increased demand. In addition all back-up and archiving was switched to a more modern system, Legato, thus greatly reducing back-up and archiving times for the ever-increasing data volumes. The EUCLID database was compacted in order to reduce data volume and improve database performance. The Pro*Engineer application was moved to the Windows platform. The engineering compute facility PaRC was upgraded with an additional five Dual CPU Linux systems as finite element codes became available on Linux. In line with the divisional RISC decommissioning, PaRC applications were customized for LXPLUS. Most engineering and mathematical applications were upgraded during the year and, where possible, made available only on Windows or Linux in accordance with the IT policy of reducing operating system diversity. Use of remaining proprietary UNIX operating systems, on the desktop and on servers, was limited to those applications requiring it. At the year’s end plans were made to integrate problem reporting with the IT Remedy system. A comprehensive licence monitoring system for engineering packages, based on Flexlm technology, the Web and Oracle, was put into production and as a result more than 30 engineering applications were monitored. A GUI tool was made available to users to enable them to better share commercial applications with a limited number of licences. Another GUI tool to enable engineers to back up and archive very large data sets coming from engineering applications and based on the CERN HSM facility CASTOR was written for Windows and Linux and will be put into production early in 2001, subject to infrastructure changes still to be implemented. A new EDMS Web interface was put into production during the year in collaboration with EST/ISS and the Finnish Tuovi team. In addition to EDMS customization and support activities, two patches were applied to the CERN CADIM installation, and the current production version was upgraded to CADIM/EDB 2.3.4. A new version of CADIM, called ‘axalant2000’, was installed and tested. A pilot project for the introduction of an interface between CERN’s EDMS CADIM/EDB and the Cadence CAE tool suite was completed successfully. The pilot installation was extended with CERN-specific customization and training material and EDMS started to be offered as a production service to the electronics design community. Automatic conversion of proprietary file formats, such as MS-Word and AutoCAD, to standard formats such as PDF and STEP, was implemented as a part of the production EDMS service. The Division was active in the CAD-2000 effort to select a future mechanical CAD tool for CERN and participated in industry visits and discussions with suppliers and vendors.

Windows Support for Computing for Engineering

Work began on porting NICE engineering applications to the Windows 2000 operating system, which was released at CERN. Many new or updated PC engineering applications were installed for NICE 95 and NT. Examples are AutoCAD 14, Microwave Studio, Ansys, Simplorer, MathCAD 2000 and Mathematica 4. Licence monitoring was introduced for PC-based engineering applications. Some servers were upgraded to

Information Technology Division 147 Windows 2000. A new remote monitoring system for the servers was installed. A PC specifically configured for engineering applications was defined in collaboration with the PC Shop, and will be available to all users in the near future. It has been targeted at design applications such as AutoCAD Inventor that require a high- performance machine offering OpenGL graphics compatibility.

CoDisCo

The Nordic collaboration project Connecting Distributed Competencies (CoDisCo) was completed at the end of the year. CERN received manpower with external funding and industrial experience. The companies in the Nordic countries that participated in the project were able to benefit from experience made at CERN with the use of EDMS and the handling of distributed projects. At the same time the project contributed to the successful start-up of a spin-off company (SingleSource) that develops and sells the Web-based document management system TuoviWDM that was developed by a Finnish team at CERN. Highlights of the CoDisCo project results are available at: http://www.nsp.ntnu.no/pages/Prosjekter/CoDisCo/index.html

Controls

Industrial Front-End Systems

OPC and CANbus are supported CERN-wide. OPC is a controls interfacing standard which is becoming increasingly important, and this was illustrated by the collaboration between IT and CAEN in the definition of an OPC server for their high-voltage power supply systems. Help was also provided to a wide variety of projects (e.g. GIF, LHCb test beam, PS-CO, CMS tracker) in the selection and use of fieldbus, PLC and OPC components.

Technical activities for CAN/CANopen support were mainly concentrated on the evaluation of CANbus interface cards from different vendors. In order to get an overview of the CANopen market, a combined workshop/industrial exhibition was organized at CERN with the attendance of representatives from 12 companies. In collaboration with the technical training service, a first course on the recommended CANopen application layer profile was held at CERN, and this course will become a standard offering in the CERN technical training programme.

Custom Front-End Systems

Despite the attraction of industrial systems, their use is not always feasible in the HEP environment. Thus, a custom front-end environment was provided, based on C++ libraries originally developed for NA48, which was also used by COMPASS. This custom front-end system communicates with the supervisory layer via the DIM communications package, which was also supported.

148 Information Technology Division SCADA-PVSS Support

Following the decision by the members of JCOP to purchase an industrial supervisory control and data acquisition (SCADA) system in September 1999, a major task during this year was to perform a full Market Survey and Tender. This led to a recommendation to the Finance Committee, which was approved in June, to purchase the product PVSS from ETM A.G. of Austria. IT Division was heavily involved in contract negotiations with ETM which led to a worldwide licence for use of the product by the LHC experiments.

Support was provided to PVSS users throughout the year, both for product evaluation and for use within COMPASS. However, since the final decision for the use of PVSS by the LHC experiments, development of a support system has started which will be capable of dealing with the large number of users expected. 40 copies of the software were downloaded. The support activities included: evaluation of new features; preparation of demonstration material; user problem handling; co-ordination of requests to ETM for consultancy, product enhancement and problem reporting; organization of training (six sessions for about 60 users so far); organization of the regular PVSS users’ meetings, setting up a CERN PVSS Web site (with licence download procedure, database and monitoring); and Newsgroup.

Experiment Support

IT provided the JCOP Project Leader, as well as supporting JCOP projects, such as GIF. Maintenance was provided for various L3 control systems until the LEP shutdown, and a system based on industrial components was produced to validate the CMS pre-shower thermal screen.

The NA48 front-end C++ libraries were adapted to COMPASS requirements and a supervisory framework based on PVSS was developed. IT staff helped supervise students from COMPASS to use these components in order to develop the first version of their control system.

The necessary changes were incorporated into the NA48 control system to reflect the modified configuration due to the loss of the drift chambers last year, and the system was run successfully throughout the beam period. IT further assisted NA48 in specifying additional functionality for the control system. Appropriate modifications were made to the existing software and these changes will be tested before being put into production. In order to concentrate resources on LHC-related development, it was agreed with NA48 to make no further changes to the current control system through to 2002, except where required because of bug fixes.

National Instruments Support

The CERN-wide site licence agreement for National Instruments (NI) software products was successfully renewed thanks to the contributions of the EP, LHC, SL, PS, EST and IT Divisions. The major events were the introduction of LabVIEW 6i, the preparation for Windows 2000, and the announcement of NI to support fully the future NI-DAQ (data acquisition) framework also on the Linux platform. In addition, at CERN’s request, NI ported the driver of the PCI-MXI2 VME interface to Linux and this was made available as a standard NI product. Also, during last year, NI remained one of the major CERN suppliers of computer software and hardware interfaces. An expanding area of the usage of LabVIEW is in equipment production, testing and

Information Technology Division 149 calibration. Many test stands are defined and developed at CERN, copied, and then sent to collaborating institutes or to firms all over the world. The usage of NI software add-on packages, such as Image Processing, Motion Control, Database Access Toolkit and Application Builder, also increased.

Embedded Operating Systems

After ensuring a smooth transition to the year 2000, OS-9 support activities were largely reduced over the year and users of the service were informed that the OS-9 support at CERN would formally terminate with the end of LEP. The majority of the LynxOS RT operating system users continued to use version 2.5.1 during the year, but the new versions 3.1.0 and 3.1.0a were installed and tested. PS Division wants to use 3.1.0a for accelerator control in 2001. The BOOTP+TFTP net boot firmware for LynxOS/x86-wd3e was cleaned up for COMPASS and was brought into use also by SL Division. With the increasing interest in the use of Linux in the embedded environment, Linux was installed on a VMEbus PC and a VMEbus PowerPC. The systems were used to investigate diskless, net booted Linux and EP-ESS Group set up a boot and NFS server for diskless VMEbus PCs and PowerPCs, using LynuxWorks’ BlueCat Linux. Real-Time Linux, a further interesting candidate, was installed and tested and the results were published on the Web.

DCS Framework Project

Given that a SCADA system is a complex toolkit, the goal of the Framework project, under the auspices of JCOP, concerned its customization to the HEP environment. This included guidelines for the integration of separately developed systems, introduction of Finite State Machines, access-control models and so forth. Its realization avoids duplication of the work by many separate experiments. Architectural design issues were dealt with by a working group which includes members of the experiments, but which was chaired by IT. A substantial document defining guidelines for development of control systems using PVSS was prepared and a number of key architectural concepts were prototyped. The first version of the Framework itself was under implementation. It will in the future take advantage of the development already carried out within the context of COMPASS.

Gas Control Systems Project

The aim of the project, run under the auspices of JCOP, is to provide control systems for the whole of the gas distribution chain (mixing, distribution, purification, recuperation) for the LHC experiments, which have approximately 24 gas systems. Thus, this project aimed to avoid a very considerable duplication of effort CERN-wide. During the year, a detailed analysis of the requirements for the systems was made in collaboration with the Gas Working Group, and evaluations were made of various candidate industrial solutions, including different models of PLCs and digitally-controlled gas hardware.

150 Information Technology Division Internet Services

Interactive Videoconferencing

The Virtual Room Videoconferencing System (VRVS), developed by Caltech in collaboration with CERN, confirmed its success in the HEP community. This system was designed for interactive multi-site meetings over the Internet. It is based on public domain applications for audio, video and document sharing, and is supported on Windows 95/98/NT/2000 and most UNIX systems.

At the end of the year, 2380 people had registered about 4000 machines in VRVS from more than 40 countries. During the year, five extra VRVS distribution nodes (i.e. UNIX computers called ‘Reflectors’) were deployed. In total 28 VRVS Reflectors are installed in Brazil, England, Finland, France, Germany, Israel, Italy, Japan, Portugal, Russia, Singapore, Spain, Taiwan, Venezuela and, of course, the USA and CERN.

At CERN, one more meeting room (40-R-D10) was equipped for videoconferencing with a PC-based system supporting VRVS Internet conferences as well as over traditional ISDN connections. The room equipment also included a complete set of audio/video peripherals.

Messaging Services

The IMAP servers were upgraded with more recent and powerful hardware. The SMTP and Listbox servers were migrated to Sun equipment, allowing for the removal of the Digital UNIX platforms in the course of 2001.

Substantial efforts continued to be needed for the day-to-day operation, noticeably because of spamming. User support was reviewed and, as a consequence, it mas moved on to a service contract for the second-level user support.

A new Web-based management interface to e-mail distribution lists (SIMBA) was introduced, making use of directory services.

On the client front, the long awaited new version of Netscape (4.7) was released.

Tests were conducted for providing the SMTP relay with authentication, so that travelling CERN users may post messages when not in the CERN network domain.

The possible use of a commercial version of SENDMAIL was investigated.

Mobility Devices

A study of the possible impact of new mobile facilities and devices (initially WAP, then PDAs) was initiated, resulting in concrete proposals to be formulated early in 2001.

Information Technology Division 151 Webcasting

This refers to the scenario where only one site is producing audio and video, all other sites being passive listeners. Recordings can be produced, and then made available via a Web interface for on-demand playback.

During the year, the pilot Webcast.cern.ch server was ported to a new PC-based platform and improved in terms of Web interface and production tools. Owing to its success in broadcasting sessions of LEPC and LEP Fest, the initial number of licences (100) was upgraded to 200 and then again to 400.

Various teams and projects involving IT Division, Outreach Committee, Academic Training Service and University of Michigan continued to populate the Webcast server with audio/video recordings and synchronized slides. These recordings were made at CERN during physics events as well as during the Academic Training Programme, Science colloquia and Summer Student Lectures.

Web Services

During the year, a new infrastructure for the Web Services was deployed at CERN allowing the automation of the registration procedures and enabling enhanced multi-platform services such as electronic forms, Web- based databases and access controls.

Second-level support was moved to a service contract.

Windows Services

A massive migration of the data stored on the home directory, project space and application servers that were stored in Novell Netware servers was achieved by migration to more powerful hardware running Microsoft Windows 2000, allowing a much better integration and an important economy of scale with the already existing Windows-based server infrastructure.

After the successful pilot project for a new desktop service, an in-depth consolidation and a production infrastructure were installed to be able to start offering native Windows 2000 desktop services during 2001.

Computer Security

CERN experienced a significant increase in the number, type and complexity of security incidents during the year. This increase matches that seen across the Internet as a whole. Hacking tools, readily available and simple to use, have become increasingly more sophisticated and the personnel effort needed to recover from incidents at CERN is growing exponentially. In order to combat this increase, a proactive approach to computer security is required across the Laboratory as a whole. IT Division has foreseen increased resources during 2001 to enhance computer security infrastructure and, together with system responsible persons across CERN, improve the security of computers on the CERN network. New rules governing the use of CERN computing facilities, available at http://www.cern.ch/ComputingRules, were introduced in October.

152 Information Technology Division Education and Technology Transfer Division

The Education and Technology Transfer (ETT) Division came into existence in January 2000. In a highly productive year, the celebrations marking the end of LEP were an important highlight, with many members of the Division contributing to their success. Senior politicians from the Member States attended the official closing ceremony which was graced with the première of a ballet specially produced for the occasion by the Rudra-Béjart ballet. Then followed a two-day science symposium on LEP physics that attracted more than 1000 participants, closing on a festive note with a party for over 3000 CERN staff and users.

Education and Communication

The Education and Communication sector was active in on-site visits, on- and off-site exhibitions, interaction with the media, CERN on the web, printed publications, and work with audiences. Towards the end of the year, a planning group examined current activities and considered possible new activities on an 18-month timescale. This work will be followed up in 2001.

Visits

The year 2000 was the last year for LEP visits, with a record of some 32 000 visitors on the regular visits programme, a 5% increase over 1999. With underground areas no longer open to the public, new itineraries were identified and their preparation begun. The volunteer guides were retrained, over 200 in number, some 80% of them being young physicists working on CERN experiments. The guides’ information kits and Website were updated as was the documentation for visitors.

Exhibitions

New hands-on exhibits were added to the Particle and Forces platform of the on-site exhibition Microcosm as part of an ongoing upgrade following evaluations carried out on the target audience. They were very well received by the press and visitor numbers have risen considerably. A revised version of CERN’s travelling particle physics exhibition When Energy Becomes Matter visited Berlin, Paris and Cracow attracting a total of 150 000 visitors. The Hadrons for Health exhibition, originally developed by the TERA Foundation, GSI Darmstadt, and EP Division, was refurbished in collaboration with GSI and INFN, Italy and shown in Lyon.

Education and Technology Transfer Division 153 The exhibition Science Bringing Nations Together on collaboration between CERN and Eastern European countries was completely updated and shown in the European Parliament in Brussels.

Media

Over 640 journalists visited CERN, by far the highest number ever. They came from all the Member States, the USA, Japan, Turkey, Thailand, Vietnam, Yugoslavia, Russia, Kuwait, Korea, India, China and Australia. In total 77 television crews passed through the laboratory. Major coverage was given to four events: the February announcement of evidence for quark–gluon plasma, the Antiproton Decelerator (AD) start-up in August, the possible sighting of the Higgs boson during the final days of LEP operation and the eventual decision to close the accelerator, the latter creating unprecedented interest in particle physics in the world’s media.

Web Presence

The Division had Web sites covering the above-mentioned major events. There were over 60 million requests for the user pages (more than 160 000 per day or 2 per second), and almost 5 million requests for the public pages (more than 13 000 per day).

Invited presentations on CERN’s role in the development of the Web were given around the world at a rate of more than one a week. CERN is still visible in the International WWW Conferences (http:// www.iw3c2.org) and ETT hosts the Euroscience web server (http://www.euroscience.org).

Two Webcasts on antimatter were organized in a Live from CERN Webcasting pilot scheme implemented in collaboration with the Exploratorium in San Francisco. Audiences of between 6000 and 10 000 from all over the world were achieved.

Publications

Some 300 000 brochures were printed, including ‘CERN the World’s Leading Particle Physics Research Laboratory’; ‘The LHC’; ‘Industrial, Medical, Research, and Future Applications of Particle Physics’; ‘Antimatter’ and ‘Where the Web Was Born’, in over 10 languages including English, French, German, Italian, Spanish, Polish, Norwegian, Danish, Finnish, Swedish, Greek and other languages on request. The popular CERN cartoon book was updated to include the LHC and another favourite, ‘When Energy Becomes Matter’, was completely revised and a French version distributed to local schools. A special brochure was produced for the LEP Fest and a ‘Grid Brochure’ was published to support the Division’s technology transfer work. At the request of PS Division, a brochure on the 40th anniversary of the PS was produced.

The Weekly Bulletin continues to be the principal vehicle for internal communication at 6000 copies per issue. Most of it is now also on the Web.

The CERN Annual Report for 1999 was produced in three volumes as usual and an on-line version of Volume 1 was produced for the first time.

154 Education and Technology Transfer Division The CERN Courier continued to thrive as part of the UK Institute of Physics collection of specialized magazines. It is edited in ETT division in French and English, the latter being available on the Web.

Communities

The Local Community

Two special year-2000 events were targeted at the general public.

The Oracle of Delphi, a show about antimatter, mixing mime, music and acrobatics, brought contemporary scientific thought within the reach of everyone. The play enjoyed considerable success with both the public and the media and has subsequently been performed at the Palais de la Découverte in Paris.

Signatures of the Invisible was a project in which 12 of Europe’s leading contemporary artists interacted with CERN theorists, experimentalists, and IT specialists to produce works of art. A particularly fruitful partnership was established with the CERN workshops. The resulting exhibition will open in London in March 2001 before a three-year tour of major European galleries.

Division members participated in several local popularization events organized by Geneva University’s Passerelle Science-Cité and the Geneva Musée d’Histoire des Sciences. These included La Nuit de la Science in July and 56 Heures pour Explorer le Fond de la Casserole in October.

Secondary Schools

The High School Teachers’ (HST) programme targets teachers, each of whom reach a large number of students. In 2000 the programme had 22 European participants financed by CERN. Portugal and Poland each funded an extra participant and the National Science Foundation (NSF) sponsored four US teachers. Many participants have since organized information days in their home countries. The ETT Information Support Unit set up a website (http://teachers.cern.ch/) for the teachers and helped them produce a CD-ROM.

Another new initiative brings teachers to CERN on three-day visits funded from external sources. The aim is to present contemporary science and technology taking place at CERN in a way that can be used in the classroom.

Physics on Stage

In November more than 500 physics teachers from 22 European countries came to CERN for a week-long Physics on Stage event, funded by the European Union as part of the European Week of Science and Technology. It was the first collaboration in communication between Europe’s three leading physics research organizations, CERN, ESA, and ESO. All countries had stands where teachers showed material used in their courses. The conference analysed the reasons for the declining interest in physics among young people and

Education and Technology Transfer Division 155 considered possible actions to reverse this trend. The event was visited by many European VIPs, including Commissioner Phillipe Busquin who encouraged the idea that it become a biennial event.

Local Schools

A new programme was developed in collaboration with the Inspectorate of the Académie de Lyon, for schools in the Rhône-Alpes region, the Canton of Geneva, and the Department of Haute Savoie. Each Tuesday is reserved exclusively for visits by local schools with a programme run by physicist-guides tailored specifically for 13–15-year-old students. It is extremely popular and has increased the number of classes visiting the Microcosm by 30%.

A joint programme was also established with the Lycée International in Ferney-Voltaire in which ETT personnel and physicist-guides visit the schools and the local schools visit CERN to work on experiments linked to the school syllabus. A new video for schools, Du Big au Bang, produced in collaboration with the French Education Nationale and the Crédit Agricole bank and financed entirely from external sources, was launched at CERN in May.

Outreach

The European Particle Physics Outreach Group held its first meeting outside of CERN in Paris in June at the time that the CERN travelling exhibition was there. This allowed delegates to give inmportant feedback to the exhibition organizers. The group also played an important role in setting up the HST 2000 programme and Physics on Stage.

Library and Archives

CERN Library

The CERN Library (http://library.cern.ch/) plays an important reference role. Its main task is to make preprints available to the world HEP community long before formal publication. During 2000, productivity in the library was improved once again. On average, more than 4000 preprints were processed per month compared to 1000 in 1995, more than 350 interlibrary loan requests were processed per month compared to 70 in 1995 and more than 1200 electronic journals are now available in full-text on-line.

A first collection of electronic books has been catalogued and several theses were loaded from collaborations’ servers onto the central Library server giving them greater visibility. The Library Web pages registered more than 7000 hits per day.

A set of newly organized services is now offered. The more important are a procedure to buy and reuse IEC and ISO standards, an electronic shelf for newly acquired books (prepared with ACCU), and a limited CD-ROM LAN service (installed with the help of IT Division).

156 Education and Technology Transfer Division Co-operation is important for the Library. It can share resources (documents), as well as staff training and development efforts. Many co-operation agreements have been negotiated both in HEP laboratories and universities in and outside Member States, ranging from a visit by one of CERN’s librarians to the Los Alamos Library to welcoming a student from a school in Ferney-Voltaire for a week of work experience.

A number of special initiatives were organized during the year, including reorganizing the CERN Legal Service library and holding a video conference with DESY and SLAC libraries about the Open Archive initiative.

CERN Archives

Steady progress was made in cataloguing the large backlog of uncatalogued material onto the Aleph database. A shelf list was also produced to enable archive staff to respond more quickly to requests for uncatalogued material and a new Working Group for Electronic Archiving was formed, involving persons responsible for improving electronic record-keeping at CERN.

The service co-operated with the ETH-Bibliothek in Zürich to produce a travelling exhibition commemorating the centenary of Wolfgang Pauli and to catalogue and digitize the Pauli Archive. The exhibition was at CERN in August and September and was seen by an estimated 5000 visitors.

Information Support Unit

The Unit collaborated with other ETT personnel to design and produce the graphics material for the LEP Fest exhibition, as well as the invitations and brochures. The photographic service made a total of 140 images of the Fest available on the Web within minutes of capture. By the end of the VIP afternoon, 3500 searches had been made in the LEP Fest photo database and about 1400 Jpeg images downloaded.

For Physics on Stage, the Unit designed and produced the posters for the CERN booth as well as videos and computer-based material presented during the event, and provided computer support for the 50 or so PCs installed in the national booths.

CERN Document Server

During 2000 several new classes of information were introduced on the CERN Document Server from LHC illustrations to Academic Training Lectures. The number of hits on the Web interface (weblib) exceeded 6 million, more than 20 000 per day, and 75–100 Mbytes of data were downloaded from the server each day.

Use of the conversion server showed a steady increase, reaching about 60 conversions per day by the end of the year, the most popular conversions being from Microsoft Word or PowerPoint into PDF.

Education and Technology Transfer Division 157 Audio-Visual Service

All conference rooms in the Main Building were equipped with fixed computer projection material. As well as continuing to provide technical support for all CERN official meetings, seminars and colloquia in the Main Auditorium and Council Chamber, the Audio-Visual service became more involved in the Internet transmission of events from the Auditorium.

Photographic Service

The use of the Document server by the photographic service continued to grow with more than 3000 records now in the database. The Service was especially active in the LEP Fest, the production of the CERN calendar, and the coverage of VIP visits.

Printing and Copying

Print production in 2000 included the three volumes of the CERN Annual Report 1999, 11 CERN ‘Yellow’ Reports, and Technical Design Reports for LHC experiments.

The year saw an important change in printing at CERN. More than 24 000 000 pages were printed on networked, high-speed Xerox Docutech copier/printers, while offset production was 14 730 000 pages. Some 153 900 pages were produced on the colour printer/copier, a marked increase over the previous year.

Desktop Publishing Service

A total of 210 documents, containing more than 13 113 pages, were handled by the service. The work included page layout, production of graphics, typing, copy-editing and proof-reading. The service became more involved in preparing brochures and posters for events both inside and outside CERN.

Technology Transfer

In its first year in the ETT Division the Technology Transfer (TT) activity was carried out by two services, which together corresponded to the previous Industrial Technology Liaison Office (ITLO), albeit with a wider scope of responsibilities to catalyse, promote and guide all aspects of technology transfer.

This year was one of exploring many new directions and possibilities to understand better where to focus priorities for the future. A particular effort was made in analysing the work processes of all of these activities, estimates of resource requirements were established whilst a new overall technology transfer strategy and plan is being prepared. Contacts with many external organizations were made in order to benefit from experience already obtained elsewhere in addressing many of the problems CERN is facing in this area. This has provided a good working understanding of the many possibilities as well as of the problems that need to be faced.

158 Education and Technology Transfer Division In April 2000 the Director for Technology Transfer invited all Members States to designate a contact person. The experience gained, particularly with those who have chosen to invest in this direction, is extremely positive and the expertise of such TT professionals has been of great value. An external TT network based on such national contacts has good potential for mutual benefit and it is intended to develop and exploit this idea during 2001. It is proposed that such designated national Technology Transfer Officers (TTOs) become the primary contact between CERN and technology transfer activities in the Member States.

The membership of the Technology Advisory Board (TAB) was reviewed and changed during the past year. The TAB considered a number of applications for patents, setting up reviews in each case. It started on the peer review of the TT-related R&D projects but the complete review cycle is far from complete. The TAB also organized a number of presentations of possible directions for technology transfer at CERN and this led to the proposal for a two-day TAB Workshop to be held in January 2001.

The Technology Transfer Service was charged with promoting technology transfer through people, purchasing, collaboration agreements, and special projects.

Technology Transfer Through People

To promote technology transfer through people, the Service developed contacts with CERN’s Nordic delegations (Denmark, Finland, Norway, Sweden) and carried out a study for a CERN alumni database.

Technology Transfer Through Purchasing

To promote technology transfer through purchasing, preliminary discussions were held and a proposal of work was prepared in the context of a SURF (Socio-economic Utility Relevant Factors) Study.

Technology Transfer Through Collaboration Agreements and Special Projects

To promote technology transfer through collaboration agreements and R&D projects, a summary was prepared of how high-energy physics technologies could be used in applications outside the domain of particle physics, and in particular to applications in the biomedical field. The following table is a summary of the status of the TT-related R&D projects supported by ETT during 2000.

Education and Technology Transfer Division 159 Status of technology-transfer-related R&D projects

Name Status Collaborators

MEDIPIX The Medipix project aims to design, test and CEA, LETI, Saclay; CERN; evaluate CMOS readout ASIC for semicon- Czech Technical University, Prague; ductor pixel detectors for single photons IFAE, Barcelona; MRC, Cambridge; Mid-Sweden University, Sundsvall; with low background. ETT has facilitated NIKHEF, Universitat Freiburg-i.B.; negotiations between Medipix, CERN, INFN, Cagliari; INFN, Napoli; NIKHEF and a large European company for INFN, Pisa; INFN, Sassari; transfer of this technology. If successful this Univ. Glasgow; ESFR. will provide financing for the Collaboration. ETT has also provided Medipix with two students and a CERN Fellow, and around 60 kCHF.

Crystal Clear Improve resolution and sensitivity of com- CERN; LETI, France; mercial PET scanners by means of: LAPP, Annecy; IIHE VUB-ULB, Brussels; –new improved crystals Copernicus Univ., Torum; Delft Tech Univ.; –avalanche photodiodes Geneva Univ. Hospital & Univ. Lausanne; –fast and low-noise readout electronics Giessen Univ.; Grenoble Univ.; –integrated reconstruction and data manage- LPCML, IPNL, Lyon; ment software. INFN Milano; INFN Pisa; ETT supported the Crystal Clear Collabora- Minsk Univ.; Moscow State Univ.; tion with one project associate, one fellow Muenchen MRI; Prague CAS; INFN, Rome; DAFNIA, Saclay; and around 120 kCHF in 2000. Valencia Univ.; Bogoroditsk Plant; Karl Korth, Germany; Hitachi Chemical, Japan; Mitsui Mining and Melting NK&k, Japan; Crytur, Czech Republic; Optovac, USA; Crismatec, France; SIC, Shangai; Le Verre Fluoré, France; CTI, USA; Scionix, Netherlands; Siemens AG, Germany.

The hybrid ISPA is a hybrid photodetector including a CERN; Imaging Sili- highly segmented pixel anode designed for INFN and Rome III University, Italy; con Pixel scintillating fibres and RICH detector for Prague Academy of Science, Czech Rep.; DEP, Netherlands; Array (ISPA) gamma imaging with submillimetre accu- Crytur Ltd, Czech Rep.; tube racy. Edgetek, France; PMB Metaceram, France; LIP Lisbon.

160 Education and Technology Transfer Division Status of technology-transfer-related R&D projects (cont.)

LIBO (LIna LIBO is a linear accelerator complement to CERN; BOoster) existing medical cyclotrons for hadron ther- INFN Milano; INFN Napoli; apy. In 2000 LIBO completed its expected TERA Foundation; Scanditronix IBA. programme with the help of a Fellow and 110 kCHF provided by ETT.

Compton The aim of this research is to CERN; camera develop techniques for precise quantifica- Univ. Michigan, USA; tion of radio isotope localization in samples Institute of Nuclear Physics, Cracow; LEPSI, IN2P3/CNRS-ULP; (in-vitro), in small animals (in-vivo), and Inst. De Fisica, Valencia Univ.; later on may be in whole-body human imag- Univ. Ljubljana, Slovenia; ing with high spatial resolution and high IDE AS, Oslo. counting efficiency. ETT has provided a PhD student for 2–3 years and about 55 kCHF

CRISTAL A distributed and integrated data manage- CERN; ment system to track product and process LAPP, Annecy; evolution. A demonstrator targeted at SME UWE, Bristol; IN2P3, Dept. Haute-Savoie. and industries is under construction. ETT provided one doctoral student, one project associate and 120 kCHF.

Ultrasonic An ultrasonic gas analyser has been devel- CERN; gas analyser oped to meet a need for radiator gas analysis Centre de physique de particules de in ring imaging Cherenkov detectors as well Marseille. as to measure perfluorocarbon vapour mixtures and xenon, helium, or nitrogen gases.

Gas Elec- GEM consists of a thin polymer foil, metal- CERN. tron Multi- clad on both sides, and pierced by a high plier (GEM) density of holes. On application of a potential difference between the two sides, electrons from a drift region are collected into the holes, multiply in avalanche, and emerge on the lower region.

Software Develop industrial strength software tools to CERN; tools ensure the high quality and maintainability Institute for Scientific and Technological of code developed for LHC experiments Research (IRST); Istituto Trentino di Cultura (TC). over a life cycle of 20 years. Total cost of the project to CERN is 80 kCHF and ETT has given 25 kCHF.

Education and Technology Transfer Division 161 Status of technology-transfer-related R&D projects (cont.)

PIMMS Proton ion therapy accelerator with beam CERN; lines and gantries. Med-AUSTRON; Design study giving details for a specific Onkologie-2000; TERA Foundation. design. Study completed and published.

ApeNEXT Development of a computer architecture CERN; aiming to provide computing power of the INFN, Roma; INFN, Parma; Roma II; order of several Tflops. INFN, Milano II; Univ. L’Aquila; ETT provided 110 kCHF in 2000 for proto- DESY. typing and also provided one project associate.

Promotional Events and Exhibitions

The Technology Transfer Service supported some ten promotional events and exhibitions outside CERN this year, including, in particular, the Swiss Microsystems Forum in London, the IEEE-NSS-MIC Conference Exhibition in Lyon, and the European Union IST 2000 in Nice, as well as the 22nd Rencontres de Blois Conference on Frontiers of Life.

The Technology Transfer Service also facilitated a number of promotional events at CERN, including notably the GigaByte Systems Network Workshop and the European School of Medical Physics. The LEP Fest Exhibition contained a major section on technology transfer, which included two demonstrations of TT-related R&D projects. The Technology Transfer Service also contributed to the LEP Fest in the organization and provision of the database. The Technology Transfer Service organized six seminars on technology transfer in the past year. It is intended to put a more structured and regular programme of Technology Transfer Service seminars in place during 2001. Useful visits were made to some university Technology Transfer Services and start-up units and the service also organized visits to CERN.

Grid Activities

The data grid has been a major activity because of the potential of obtaining resources for CERN and particle physics from funding outside particle physics. The efforts of the Technology Transfer Service team were particularly focused in promoting the general-use aspects of data grids via presentations, brochures and many articles in leading newspapers and scientific journals.

In addition, considerable effort was made in helping the IT Division to investigate funding for the data grid from sources beyond particle physics. An important initial step in launching the grid activity as a real working project is the recent signature of the DataGrid contract. The DataGrid Project proposal made to the European Commission for shared cost research and technological development funding resulted in funding of 9.8 M• over three years.

162 Education and Technology Transfer Division The requirement that the gridfor particle physics and LHC computing should be compatible with, and useful to grids for other disciplines, led to considerable efforts to promote the grid within other sciences and industry. Particular efforts were made to assist the bioinformatic community to form a collaboration and prepare a proposal for funding a Bio-Grid which can be submitted to the EU. A major success was getting EU Commissioner, Phillipe Busquin, UK Minister of Science, Lord Sainsbury, and the Director General of the UK Research Councils, Dr J. Taylor, to meet the CERN Director-General and Directors Hans Hoffmann and Roger Cashmore during the LEP Fest event.

Intellectual Property Rights

The Intellectual Property Rights (IPR) Group was charged with implementing the pro-active technology transfer policy of claiming, promoting, and organizing IPR and its subsequent licensing.

Patenting and Licensing

In order to promote technology transfer through patents, an important task of the Group is the maintenance of the CERN patent portfolio, which was expanded from 10 to 12 patents in 2000, and three patents are in the process of being filed.

Maintaining the portfolio involves licensing CERN patents as well as filing new patents. In 2000, one licensed patent was billed and the Patent Co-operation Treaty (PCT) extension of three patents was requested. The licensing of one patent was finished and studies were made of applications of the same technology for future potential technology transfer collaboration agreements. A market study was completed for another patent, licensing was subcontracted for two important application areas, and the market survey and licensing was initiated for a further patent. The following table lists the patents currently in the portfolio.

Patent portofolio

Date filed Title Ownership Country where Status initially filed

A thermal management device and CERN + Queen Mary 08 Jul. 1998 PCT international method of making such a device and Westfield Col- United Kingdom examination lege, University of London

Gas Electron Multiplier (GEM) CERN 22 Oct. 1997 PCT international Radiation detector of very high per- 09 Sep. 1998 search phase formance and planispherical parallax USA 16 Oct. 1998 Europe

Coquille de reniflage CERN 15 Dec. 1999 PCT request France

Education and Technology Transfer Division 163 Patent portofolio (cont.)

Cryogenic monolithic semiconductor CERN + Universität 01 Jul. 1999 PCT request, detector Bern, Laboratorium United Kingdom started the PCT für Hochenergie international search Physik

Polissage électrochimique titane CERN 25 Jun. 1999 PCT request, PCT France international examination

Pumping device by non-vaporizable CERN 19 Jun. 1996 National phase getter and method for using this get- France ter (NEG surfacique)

Arrangement and method for improv- CERN 26 Feb. 1997 National phase ing vacuum in a very high vacuum France system (Catalyseur surfacique)

Neutron-driven element transmuter CERN 19 Jun. 1997 National phase PCT: Europe, USA, Japan, Can- ada, Norway etc.

Diaphragm system CERN 21 Oct. 1999 PCT request Europe

Device and method to measure a CERN 22 Jan. 1988 Protection main- short radiation pulse or an electric France tained in some pulse countries only

Tête + support interchargeables CERN 18 Apr. 2000 Filed France

A semiconductor device CERN 18 Dec 2000 Filed United Kingdom

The accumulated income from licensing is still insufficient to cover the total costs of the patent portfolio. Although patents producing royalties are few in sciences except in bio-sciences, patents can produce financial rewards for individuals collaborating with CERN and can act as an incentive for research and development. Moreover, shared patents play a role in linking partner institutes in further developments with CERN.

In order to promote CERN technologies through licensing, contacts were established with the Industry Liaison Officers (ILOs) of the Member States. In addition, contacts were made with commercial technology promoters and web sites that advertise technologies for licensing.

In promoting technology transfer through agreements, five collaboration agreements and one consultancy agreement were prepared and/or followed up with industrial partners and other academic institutes. The conditions and rates under which CERN employees provide consultancy were reviewed and corrected for inflation.

164 Education and Technology Transfer Division Technology Transfer Through Start-Ups

In order to learn the best practice in the promotion of start-ups and spin-offs from a public research institute, CERN is participating in the Expertise on Setting up Innovative Firms Project (EXSIF). EXSIF is supported by the European Commission under the Fifth Framework Programme. CERN is involved in EXSIF largely on account of its experience of managing international research. In return CERN will benefit from the technical and specific expertise of the different partners in setting up spin-off companies nationally, which in turn will help CERN in developing its own start-up/spin-off process. EXSIF partners have presented start-up candidates to be selected as test cases that will be followed up. There are 26 candidates, 3 of which are from CERN.

Technology Database

The CERN technology database has been improved and upgraded to provide easy public access to the CERN technologies, to complete the technological content on the basis of personal contacts with CERN physicists and engineers, to manage all the enlarged TT activities with the appropriate authorization level access, and to be compatible with the existing database and the tools for storing and accessing information. In addition, a network of CERN technology experts as contacts has been established within the technology database. These people are extremely important in order to understand which technologies CERN has available for exploitation. During 2001 it is intended to develop this network further and to build activities that bring these experts closer to the TT processes and promotion.

Education and Technology Transfer Division 165

Large Hadron Collider Division

The division’s main focus in 2000 remained the final definition, industrialization, and procurement of components for the main accelerator systems of the LHC, i.e. superconducting magnets and their ancillaries, cryogenics, vacuum, and industrial controls. As an illustration of this intense activity, it is worth mentioning the 14 engineering design or production-readiness reviews held over the year, as well as the 34 additional contracts submitted for adjudication to the Finance Committee, for an overall value exceeding 300 MCHF. The division also continued to provide full support to the operation, development, and upgrade of the cryogenic and vacuum systems of the CERN accelerators and physics experiments, a particularly demanding task in this final year of LEP operation at very high energy. The activities of the eight technical groups are reported in detail in below.

Cryogenics for Accelerators

Cryogenics for LEP and SPS

The final intervention on the refrigerator at Point 4 of LEP for the cooling capacity upgrade was successfully done during the 1999/2000 shutdown and the achieved capacity enabled LEP to run reliably with all four cryoplants.

Although the clogging phenomenon of the turbine filters, especially in two plants, could be reduced after an extensive cleaning of the circuits, it still could not be eliminated and caused some downtime. Nevertheless, the constant follow-up of the problem and co-ordination with the operation team allowed the optimization of the LEP running time for machine development and high-energy physics time.

To avoid any oil leakage from the compressor circuits to the environment, the compressor buildings were modified in order to act as possible oil retention ponds. The excellent performance of all accelerator systems allowed LEP to run reliably up to an energy of 104.5 GeV. The running of the cryogenic systems of LEP and SPS were very successful. The number of cryogenics availability hours lost resulted in a mere 1.98% loss of LEP 2000 running time, to be compared with the 3.68% lost in 1999.

After the announcement of the decision to stop LEP, the plan for the dismantling, prepared beforehand, started with the safety measures necessary to ensure safe dismantling. First cuts on the cryogenic equipment were already performed in 2000 to prepare dismantling in 2001.

Large Hadron Collider Division 167 Cryogenics for the LHC

It was decided to install the LHC full test-cell in SM18 (String 2) in two phases, firstly with two quadrupoles and three dipoles until May 2001 and secondly with all machine elements needed for a full cell beginning of 2002. In addition to the cryogenic infrastructure such as liquid helium supply lines, distribution box and a quench buffer volume already installed and commissioned, cryogenic equipment is needed to cope with the partial set-up of the String 2 assembly.

After an upgrade of the cryogenic infrastructure for the magnet test plant in SM 18 with the installation and commissioning of all sections of a new compound cryogenic distribution line to serve up to twelve test sites, several departures of this line were used to serve installed magnet test stands or temporary cryogenic test facilities such as the US-supplied experimental set-up for testing the heat exchange of the future cryo-loops for the inner triplets or the Cryolab Large Test Facility (CLTF).

Two Cryogenic Feeder Unit prototypes (CFUs), are now fully operational for the series testing of LHC dipoles and quadrupoles. The original contract which also included the delivery of the series CFUs was terminated and new contracts for 12 Cryogenic Feed Boxes (CFBs), of final design and their cryogenic current leads, were awarded to an expert firm. The first two CFBs are scheduled to be delivered in 2001.

To cool the magnets to the required very low temperature, eight 2.4 kW at 1.8 K helium refrigeration units using cold hydrodynamic compressors are being manufactured by IHI/Linde (Japan/Switzerland) and Air Liquide (France). The units will be delivered from spring 2001 onwards, technically validated on a cryogenic test stand before being installed underground and linked to the different 4.5 K cryoplants. The cryogenic infrastructure for the test stand in the P1.8 area and the link to the neighbouring cryoplant as well as the associated control system were undertaken.

The manufacture of the four new large helium refrigeration plants for the LHC, each of an equivalent cooling capacity of 18 kW at 4.5 K is well in hand. The helium compressor station of the first plant has been installed in point 1.8 and first test runs were made. Buildings to house further helium compression stations and cold boxes are nearly finished or will be finished after shutdown of the LEP cryoplants. Pipe-work for gaseous helium and cooling water for all surface sites and shafts was contracted to industry.

For the partial storage of the helium inventory and possible gas recovery from magnet quenches, 20 out of the 30 pressure vessels (250 m3 at 2 MPa) ordered were installed and pressure tested, monitored by acoustic emission, in addition to the 12 vessels recovered from LEP. The remaining 10 tanks as well as an additional 10 vessels recently ordered will be delivered in 2001/2002.

Ten 50 000-litre liquid-nitrogen storage tanks were ordered. They will be installed at the five cryogenic sites around the LHC and serve the refrigeration plants and their full-flow dryers as liquid nitrogen buffer volumes.

A major item of the cryogenic system still to be procured is the Cryogenic Distribution Line (QRL) running in parallel to the magnet cryostats, feeding all cryogenic consumers with helium at different temperatures around the whole machine circumference. As an intermediate milestone in the procurement procedure of the line, qualifying pre-series test cells of approximately 110 m length were delivered and

168 Large Hadron Collider Division installed on a test stand at CERN for extensive testing, before final tendering with the qualified firms for the total QRL of 26.7 km length. Qualification tests on two test cells were done and the third one will be finished by March 2001 followed by the final tendering. This phase will be concluded by critical design reviews.

The procurement procedure for five cryogenic interconnection boxes linking all main cryogenic components to the cryoplants and distribution system is engaged.

After prototyping of cryogenic components such as superfluid helium relief valves, sub-cooling heat exchangers, flow-meters and flow regulated control valves, final technical specifications were written and the procurement procedures partly launched.

High-accuracy cryogenic temperature sensors are needed for the precise measurement of the magnet cold mass temperatures. Six thousand of them were ordered and 15% already delivered. Their signal conditioners as well as prototype pressure transducers, which have to withstand the working conditions of the machine tunnel, are still under irradiation tests.

The PLC-based industrial process control system, UNICOS, and its associated software for the control and supervision of the cryogenic equipment of the LHC accelerator and the LHC experiments were ordered from industry within the estimated budget. The objective is to ensure a homogeneous support and maintenance policy aiming at an operation of the different cryogenic systems by a single team.

Cryogenics for Experiments and Test Areas

Cryogenic Support for LEP2 and Fixed-Target Experiments

In the SPS North Area, helium refrigeration was supplied to three experiments using superconducting detector magnets: NA49 (two magnets), CMS-RD5, and ATLAS-H8. Total operation time was 10 000 hours.

For LEP2 experiments, DELPHI and ALEPH superconducting solenoids with the associated low-β quadrupoles completed their last physics run and the two cryogenic plants, operated for more than 100 000 hours over the last 12 years, are now being dismantled.

Liquid helium and liquid nitrogen cryogenics were upgraded for the COMPASS experiment in order to be ready for first operation in 2001.

For the new CAST experiment, preliminary studies were carried out in order to evaluate the cryogenic needs. The DELPHI cryogenic plant will be re-installed at the surface of LHC Point 8, providing the required 4.5 K cooling capacity.

Cryogenic Support for LHC Experiments

CMS experiment The external cryogenic plant (supplied by Air Liquide) for the large superconducting solenoid is under construction, and delivery and commissioning of the first components is expected in 2001.

Large Hadron Collider Division 169 Layout and integration studies together with all the necessary infrastructure facilities were completed for testing the entire plant at the surface of LHC Point 5 prior to the commissioning of the magnet.

ATLAS experiment The ECR group continued to provide technical support for the operation of three test benches running on the H6 and H8 beams of the EHN1 experimental hall for testing the prototype and pre- series modules of the liquid argon calorimeters.

The helium cryogenic facility in the West Area (Bldg. 180) for testing the superconducting toroids of the barrel magnet was completed and almost entirely commissioned. First operation of a prototype model magnet (B00) powered via 20 kA current leads was achieved. The cryogenic infrastructure is now ready for allowing testing in 2001 of the B0 prototype magnet delivered at the end of 2000.

Detailed studies were pursued to provide, in the same area, a large test facility for the final liquid argon calorimeters (barrel and end-caps) and the central solenoid.

The design of the common external cryogenic system of the ATLAS magnets at LHC Point 1 is completed and a technical specification for a new cryoplant prepared.

Support was given in the design of the proximity cryogenic system for the toroidal magnets (barrel and two end-caps) in close collaboration with RAL.

Advisory work was provided to KEK for the proximity system of the central solenoid. Much effort was devoted to co-ordinating and supervising the collaborations established with several external institutes for the cryogenics of the liquid argon calorimeters namely:

– BNL (USA) for the nitrogen refrigeration system,

– LAL (Orsay) for the control system,

– ISN (Grenoble) for the proximity cryogenics,

– NTNU (Norway) for the liquid argon and liquid nitrogen dewars.

The integration and the design studies followed by the preparation of a technical specification of the majority of the final components were completed.

Cryogenic Support for Test Facilities of LHC Magnets and RF Cavities

In 2000, the ECR group continued to operate three test facilities for the cryogenic components of the LHC.

1) The SM18 large area with two 6 kW helium refrigerators (Air Liquide and Linde plants) with the associated recovery and purification units. Total running time was 8000 hours (84% Air Liquide plant). This facility supplied liquid helium to:

– the LHC full-sized magnets test benches and LHC R&D test area;

– the test benches of superconducting cavities for both the LHC and other future accelerators;

170 Large Hadron Collider Division – mobile dewar (10 000 litres) filling station. Total number of dewar deliveries is 29 with an average filling of 7000 litres.

A technical specification was prepared for a 250 m long transfer line, which will make the link with the first new LHC large cryoplant of 18 kW at 4.5 K, so as to increase the liquid helium production in the SM18 area.

2) The Bldg. 892 test area for short model magnets where a new helium distribution valve box was designed and is now under construction.

3) The Bldg. 163 area for the tests of LHC superconducting cables. This facility was extensively operated for the first time during 5000 hours.

Central Cryogenic Laboratory

The activities of the Central Cryogenic Laboratory (Cryolab) on R&D work for CERN-wide cryogenic applications include small-sized thermal, hydraulic and electrical tests in a cryogenic environment, the conception and design of cryostats for special customer applications, calculation of thermal and hydraulic systems, advisory work in reviews of technical specifications, and participation in design working groups. During 2000, 18 experimental projects were run by the Cryolab, of which 10 continued from the previous year. In addition, 13 tests, of which 5 continued from the previous years, received the active support of the Cryolab but were run directly by the customers. A full-scale (15 m long) test facility reproducing the same pattern of temperature levels as the LHC dipole cryostat was constructed and operated in SM18 to measure the corresponding heat loads down to 1.9 K. As every year, the practical part of one cryogenics course and two safety courses were held at the Cryolab, confirming its role in training and education in cryogenics.

Supply of Cryogenic Fluids on Site

The central liquefier totalled 6000 hours of running time, with 240 000 litres of liquid helium distributed via mobile dewars to about 40 customers. The recently installed helium recovery and purification plant with 400 Nm3/hr capacity, associated with the central liquefier, was extensively operated recovering 600 000 Nm3 of helium. A new liquid helium buffer dewar of 5000 litres was installed in parallel to the upgrading of the gaseous helium recovery system which was linked to the existing facilities in the West Area.

5400 tonnes of liquid nitrogen were supplied to the various users to 19 large liquid nitrogen storage dewars in operation on the CERN site. The upgraded safety devices (closing valves against excess fill) of the dewars performed well.

A technical specification was prepared for the supply, over the next three years, of the helium required by the operation of CERN-wide facilities.

Large Hadron Collider Division 171 Operation of CERN-Wide Cryogenics

A technical specification was completed and the corresponding contract covering the CERN needs over the next four years was assigned to the Air Liquide/Linde/Serco consortium.

Main Magnets and Superconductors

Superconducting Cables

The procurement of the niobium–titanium alloy bars and of the niobium sheets for the three European strand manufacturers is progressing well according to schedule. Close to 28% and 33% of the total quantities of niobium–titanium alloy bars and niobium sheet, respectively, were delivered. The superconducting (SC) strand manufacturers completed the upgrade of their manufacturing facilities necessary to cope with the required large-scale production of uniform quality. They also substantially increased their staff.

The series production of the two SC strand types (type 1 and type 2) started at the premises of two European contractors and of the Japanese one. About 4.3% and 2.3% of the respective total strand 1 and strand 2 quantities were produced. These quantities correspond to 242 unit lengths of cable 1 and 141 unit lengths of cable 2 (four unit lengths of each cable type are necessary for one double-aperture dipole magnet). The other two contractors show some delay in their strand fabrication schedules.

In the companies that have started their cable deliveries, a few billets were rejected on account of strand breakages. The breakage of strands during manufacturing (a difficulty affecting the overall production yield) was addressed by the firms through a systematic effort to avoid contamination by foreign particles at critical manufacturing steps. A reduction of the number of breakages was achieved, but further efforts are needed. The specified physical and dimensional SC strand characteristics are achieved regularly, although it appears that the residual strand magnetization must be closely monitored in order to minimize field imperfections in the LHC.

The full control of the industrial coating process and of the heat treatment of the finished cable, necessary to achieve the required inter-strand contact resistance in the cable, was achieved in three companies.

The implementation of satistical quality and process control procedures, at the various steps of fabrication, is progressing well.

Two cabling machines are running regularly with two or three production shifts. The running-in of the third cabling machine, which has been designed for high productivity, is progressing. In 2000, it was possible to deliver cables for the first 18 pre-series dipole magnets (1.5% of the total quantity) to the cold mass contractors.

The SC strand and cable test facility at CERN is operational and ready to cope with the large number (up to 30 000 per year) of various measurements of physical and dimensional characteristics. These measurements are part of the contractual acceptance tests agreed between CERN and the five SC cable suppliers.

172 Large Hadron Collider Division Short Model Dipole Programme

The 1 m long dipole model programme was focused on double-aperture units. Four new double-aperture models and seven variants were assembled and tested. The main aim was to achieve a better understanding of the design and assembly parameters that govern the training behaviour of the coil ends. This turned out to be a point needing further attention because of the magnetic field enhancement in the coil ends of double-aperture magnets. The impact of coil pre-stress, length of the magnetic yoke, geometry and number of end spacers, and coil winding techniques could be studied in detail, providing precious feedback for the manufacture of the pre- series dipoles. One single-aperture model was also assembled and tested to ascertain the merits of a different resin for the impregnation of the coil ends.

Full-Length Prototypes and Pre-Series Dipoles

The delivery of the six full-length prototype collared coils ordered in 1998 was completed by September and the assembly at CERN of the first five dipole cold masses was completed by December 2000. The last prototype will be completed by mid-2001. In the course of the year the tests of the second, third, fourth, and fifth prototype cold masses were carried out.

All prototypes exceeded easily the nominal field of 8.3 T and reached the ultimate field of 9 T. Quenches occurred only in the coil end regions, confirming the soundness of the coil cross-section design. The last prototype comfortably exceeded the nominal field on the first quench and the ultimate field of 9 T with at most two quenches.

Concerning the manufacture of the 3 × 30 pre-series units, the three contractors made large investments to equip dedicated manufacturing halls with the necessary facilities and specialized heavy tooling.

The first units are delivered as collared coils, to be assembled into complete cold masses at CERN mainly by the contractors’ staff with the participation and guidance of experienced CERN staff as foreseen in the contracts. In this way the experience gained at CERN in the course of the prototype work is transferred to industry. In parallel the staged commissioning of heavy welding presses at the contractors’ facilities is progressing well, with some minor delay, but which is not expected to affect the delivery plan of the cold masses.

The first pre-series collared coil was delivered in October and a second one in December by one contractor; the first cold mass was completed in December. The first collared coils from the other two contractors are expected to be delivered in February 2001. Given the CERN tooling and resources, it is expected that the corresponding cold masses will be assembled by April and May 2001, respectively. Cold mass assembly is expected to start at the contractors’ premises in the first quarter of 2001.

With a view to ensuring a fast transition from pre-series to series production, CERN is equipping each of the three dipole cold mass contractors with a second complete manufacturing line for the winding, curing, and assembly of the coils. These lines are expected to be operational as from the beginning of 2002. On the other hand, 29 contracts for component procurement are at present in operation. Five other contracts are expected to be signed by June 2001.

Large Hadron Collider Division 173 Superconducting busbars

The manufacture of dipole cold mass busbar sets by the Budker Institute of Nuclear Physics (BINP), Novosibirsk has started and the first sets were delivered before the end of September.

An agreement for the manufacture of the busbars for the arc short straight sections was also signed with the Budker Institute.

Arc Quadrupole Magnets

Within the framework of the special contribution by France to the LHC Project, CEA-Saclay delivered the second prototype quadrupole to CERN in March. The third and last prototype will be delivered to CERN by January 2001, after full testing at Saclay. The training performance of the first two prototypes is fully satisfactory. The first had only one training quench below the nominal gradient of 223 T/m and exceeded the ultimate gradient of 241 T/m after the third quench. The second one had its first quench well above nominal gradient and exceeded the ultimate one after this first quench. The field quality of the prototypes, measured both at room temperature and in cold conditions, is satisfactory and is coherent with the mechanical and geometrical characteristics of each prototype.

The supply of 400 main superconducting quadrupoles and the assembly of the cold masses for the LHC arc short straight sections were adjudicated to a single firm for a total amount well within the budget estimates.

Apart from the austenitic steel for the collars, most of the materials and components provided by CERN will be procured within the framework of contracts established for the dipole magnets.

Magnet Quality

In the course of the year the setting-up of computer models allowing the statistical simulation of the field quality performance of dipole and quadrupole magnets was completed and validated by measurements on models and prototypes. These computer models provide the necessary means for the evaluation of magnet performance, for detecting trends, and proposing effective corrective actions in the course of series manufacture.

The field quality of the prototype dipoles was measured both at room temperature and in cold conditions. The results were coherent with the mechanical and geometrical characteristics of each prototype. They were used to propose minor modifications in some key components (yoke insert or copper wedges) required to optimize the field-shape for the series production.

Finally, the commissioning of various highly specialized devices, either procured from industry or developed at CERN for the quality inspection and control of components and completed cold masses, progressed satisfactorily. These devices will be used at the industrial premises for the contractual series inspections before delivery, and at CERN for the provisional reception tests, before the final cold test of the cryomagnets.

174 Large Hadron Collider Division Measuring Equipment

A new optical instrument, developed with industry and the Ecole Polytechnique Fédérale de Lausanne (CH), was used to measure possible movements between the cryostat and the cold mass during transportation, cooling down, excitation, quench and warming up. It is based on an interferometric method and has an accuracy of a few microns. Unexpected transient deformations of up to two millimetres were observed in three prototype dipoles during the thermal transients. Sixteen optical devices were built and will be installed in three cryodipoles and one short straight section of String 2 with a view to studying cold mass deformations in more realistic conditions.

The development of the equipment for the series measurement in industry of the field-shape harmonics of the dipole cold masses at room temperature was completed. All major components for the six measuring systems to be provided to industry and the two to be used at CERN were ordered and received.

Three devices to measure the field-shape harmonics of the main quadrupoles at room temperature were built and tested. Two of them will be used to equip the manufacturers in view of series production. A third one was provided to the SL Division for magnetic measurements of the MQW warm quadrupole magnets. Courses were organized to train staff in its installation, operation, calibration, and maintenance.

A system to measure simultaneously the geometric and the magnetic axes was completed. It can be used for dipoles, quadrupoles, or high order multipoles with minor adaptations. The preliminary tests, performed both on dipole cold masses and short straight section assemblies, demonstrated that this instrument is well- suited for the final acceptance tests during series production.

A large number of search coils and integrators were built for the cold measurements of short models and full-length magnets carried out by the MTA Group.

Database Activities

The design and the implementation of the database for the data collected during the magnet procurement are continuing. A traveller will contain the data collected during component production and cold mass assembly. For each operation the traveller will contain legal paper documents and data files with results of measurement stored in ExcelTM tables. A subset of these tables has been prepared; it includes filters for checking the data integrity. The traveller for cable procurement is almost complete. Forms for billet approval and strand tests have been made available and are routinely used by the cable manufacturers. The procedure for data transfer has been implemented, taking into account the severe requirements on data confidentiality.

Large Hadron Collider Division 175 Insertions, Correctors and Protection

LHC Insertions

The activities in 2000 were focused on further refining the system design of the insertions, as well as on the completion of the development programme of the insertion quadrupoles and launching of the series production. The layout of the LHC arcs and insertions was updated according to the optics version 6.2 of the LHC. The detailed designs of the various cryomagnet assemblies were developed and their integration with the cryogenic, powering, and civil engineering infrastructure updated.

Concerning insertion quadrupole development, a fully instrumented 1 metre long, 6 kA two-in-one insertion quadrupole with a bore of 56 mm (MQM) was completed and thoroughly tested. A 1 metre long, two-in-one 70 mm aperture quadrupole (MQY) was also fully tested. Both magnets performed particularly well, exceeding in a few quenches their ultimate current in the LHC. On the basis of these results, the technical specifications for the series quadrupoles were completed. Preparations for prototype manufacture and series production are now under way.

The collaboration with Fermilab and KEK on the design of low-ß quadrupoles has progressed very well. In both laboratories the development programmes have been completed. The final model magnets performed exceptionally well, surpassing the operating current in the LHC on the first training quench at 1.9 K. Full- length prototypes are now in the final completion stage in both laboratories. Considerable advance has been made with Fermilab, KEK, and LBL in the integration of the low-ß triplets and details of the interfaces. In a similar way, the collaboration with BNL, which has completed two prototypes and started building the series superconducting separation dipoles, has progressed well.

Corrector Magnets

The contracts for the procurement of all LHC corrector magnets have been placed with industry. Six new contracts were placed in 2000 for the supply of the combined chromaticity sextupoles and lattice corrector dipoles (MSCB), the tuning and correction quadrupoles (MQT/MQTL), the lattice octupoles (MO), the dispersion suppressor correction dipoles (MCBC/MCBY), and the inner triplet dipole (MCBX) and skew quadrupole correctors (MQSX). Together with the four already existing contracts of spool correctors for the main dipoles (i.e. the MCS sextupole and the MCDO octupole–decapole correctors), the total quantity of corrector magnets adds up to 2500 single-aperture and 1300 twin-aperture units. The supply of the enamelled superconducting wire for the series manufacture of the magnet coils is taking longer than expected to achieve the required quality. However, manufacture of pre-series magnets is progressing, using previously purchased wire for prototyping. The first pre-series magnets (MCS) were delivered and tested. Firms were also supplied with magnetic measurement equipment for checking field quality at room temperature and with quench detection equipment used for cold testing at the factory.

In parallel, work continued on a number of prototypes to check and finalize detailed design options as well as to ensure experimentally that the adopted quench protection schemes will safely protect the magnets in the different powering configurations encountered in the machine.

176 Large Hadron Collider Division Current Leads

Measurements to qualify the behaviour of High Temperature Superconducting (HTS) prototype current leads were completed. In total, nine pairs of 13 kA and 11 assemblies, each composed of four 600 A leads, were tested. Thermal and electrical cycles were made to prove the long-term viability of HTS materials in such current lead assemblies. A number of HTS materials were tested, notably BSCCO 2223 PIT Ag-Au tapes produced by several manufacturers, as well as different BSCCO and YBCO materials in the form of bars and rods.

For installation in the String-2 test cell, seven 13 kA and twenty-eight 600 A leads, taken from the prototype production, were prepared. In the frame of the CERN–US Collaboration, 42 HTS current leads of 7.5 kA, based on the CERN development, are being produced in industry and the first pair will be tested in CERN in spring 2001. A collaboration was set up with the Kurchatov Institute (Moscow) for the study of the radiation resistance properties of different HTS materials. The design of the conduction-cooled dipole corrector leads was finalized and two assemblies of four 60 A leads were installed in two prototype short straight section assemblies.

Magnet Protection

Good progress was achieved in the fabrication and testing of pre-series equipment for quench protection and energy extraction for the different LHC magnet systems. This includes quench heaters and quench heater power supplies made by European industry, as well as the energy extraction equipment, done in collaboration with the Russian institutes IHEP (Protvino) and BINP (Novosibirsk), for the 13 kA main magnet circuits and the 600 A corrector magnet circuits. The qualification tests, as well as long-term reliability and lifetime tests, are advancing well with satisfactory results. This equipment, which is representative of the final LHC design, together with the required electronics, will be available in time for the String-2 test cell experiment. In parallel to this, the series production of the protection diodes for the main dipoles and quadrupoles as well as the cold testing of the assembled diode stacks is now well under way.

Radiation tests were performed at the SPS North Area target zone on a variety of electronic components and devices, including one heater power supply prototype, in order to guide the technical choices for compliance with the LHC radiation levels. The results are promising and the heater power supply was properly working up to 380 Gy fulfilling the LHC requirements. Simulation studies completed by the analysis of experimental data of the quench behaviour of LHC magnets allowed us to finalize the protection schemes and to define the required equipment components for all circuits of the LHC machine, including those of the corrector magnets.

A prototype superconducting busbar cable to power the insertion quadrupoles at 6 kA was developed in collaboration with IHEP (Protvino) and successfully tested at CERN. Two versions with six and 18 × 6kA cables were tested. Several experimental runs carried out with these busbars as well as with the already existing 42 × 600 A busbars allowed us to determine their behaviour in case of a quench and to validate their design for the given applications. Other activities in this domain include the qualification of splices in superconducting busbars and cables, evaluation of methods for quality assurance of these splices and interconnects, studies of transmission line effects in the LHC powering chains, etc.

Large Hadron Collider Division 177 Magnetic Field Calculations

The field computation section (MF) provides CERN-wide support for magnetic field computations and magnet optimization using the CERN-ROXIE program package. The program package was upgraded for the calculation of superconducting filament magnetization, solenoids, and permanent magnet materials. A new parametric mesh generator for higher-order quadrilateral finite elements was developed at CERN and combined with the BEM–FEM method that couples the finite-element technique (inside the iron yoke) with the boundary-element technique in the air region. This implies that the air regions do not need meshing and that artificial far-field boundaries can be avoided. Based on this method, a model for the superconducting filament magnetization was implemented, which allows the calculation of hysteresis effects in superconducting magnets and the taking into consideration of local saturation effects in iron domains. Another activity of the section is the development of approximation schemes for the objective function formulation in mathematical optimizations of magnet designs.

On the design and evaluation side, the section was involved in finalizing the main dipole cold mass geometry and in setting up a database of computational models for all corrector and insertion magnets.

Magnet Test and Analysis

As in the past, intensive test programmes with tight schedules were pursued in both the MTA test plants, one in ‘Block 4’ (Bldg. 892) for the short model magnets and the other in SM18 (Bldg. 2173) for the LHC dipoles and short straight sections.

While the number of tests of short model dipoles (12 test runs) remained about the same as in 1999, the test sequence for corrector magnets, diodes and model quadrupoles increased, as expected from the overall evolution of the LHC programme. In parallel, the CERN-built test benches for the warm measurements of the MCS and MCD corrector magnets were commissioned. They were shipped to the manufacturers of these magnets in Spain (ANTEC) and to the CAT laboratory (India) where they are now being operated to qualify the first series magnets.

Preparations are in progress to test the first LHC quadrupoles in a newly designed vertical cryostat, before cryostating, allowing for an early assessment of the performance and the field quality in 2001.

In SM18 two test benches were fully commissioned together with the prototype supply boxes (CFUs). In total four prototype dipoles and two short straight sections underwent extensive tests, each including several thermal cycles. These tests provided valuable feedback and input allowing the magnet design to be finalized as well as the test equipment and procedures to be used during series tests. In particular, for the cold measurements of the quadrupoles, a newly developed and unique system was commissioned which allowed us to measure simultaneously and with high precision the field, harmonics, direction, and the centre of a quadrupole. A large amount of data were acquired allowing for a detailed assessment of the performance of these quadrupoles.

The test teams, already working partially in shifts, were supported by operators from India within the framework of the LHC–India Collaboration. This support is expected to increase in the coming year during the

178 Large Hadron Collider Division pre-series and the series phase when six operators will be at CERN at any time. In parallel, a contract with European industry is being prepared to provide the remainder of the work force to man the test teams, working around the clock during the series phase.

An in-depth review with international participation from Germany, Japan and the USA was held to verify the test programmes, the procedures and the means for the series tests. This greatly helped to clarify the subject and define clearly the strategy and procedures. As a result, twelve test benches were recommended to cope with the delivery schedule of the series magnets. The recommendations from this review are now being implemented and market surveys and price inquiries for the required hardware are being launched to be ready and fully operational for the series measurements as of the year 2003.

Cryostats and Ring Integration

The year 2000 has seen the finalization of the design and of the specification of most of the standard arc components, assemblies and subassemblies, and the launching of most of the large market surveys and invitations to tender. Up to 70% of the standard arc cryostat systems were contracted or adjudicated in European industry in 2000, representing a total amount of 97 MCHF.

This concerns the contract for the 1250 dipole vacuum vessels, under which the first 50 series vessels should be delivered in 2001. Eight pre-series vacuum vessels were delivered under a separate contract, of which five have been used to assemble the last five dipole prototypes. The 1250 dipole thermal shield contract was attributed, and the first series assembly delivered. The contract for the 360 standard short straight sections was signed, and the organization work started.

In addition, large adjudications of components done in 2000 concern the cold support posts for the arc cryomagnets (~5000 units), the 150 arc cryostat insulation vacuum barriers, the dipole multilayer superinsulation blankets (1250 sets), and the interconnection bellows between arc cryomagnets (more than 19 000 bellows with diameters ranging from 80 mm to 1100 mm).

In preparation for the series assembly production and testing of the LHC cryomagnets, a market survey to European industry was made and the specification was written for the supply contract of the work packages ranging from cryodipole and special SSS assembly, preparation for tests and connection to the test benches of all cryomagnets, up to the final preparation for assembly in the tunnel.

The new SMA 18 building, funded by the Conseil Général de l’Ain within the framework of the special contribution of France to the project, was completed and its infrastructure is being set up to host the assembly and preparation of the series cryomagnets. Following an invitation to tender, the adjudication of the five heavy cryostating toolings to be installed in this hall in 2002 is being prepared. A number of invitations to tender for orbital welding and cutting machines, rolling and bending machines, and transport and handling equipment required for these work packages were launched. The first special handling vehicle for cryomagnets was received at CERN.

Large Hadron Collider Division 179 Concerning design, the Instrumentation Feedthrough Systems for arc cryomagnets (IFS) was completed and validated by cryogenic and electrical type tests. A market survey was launched for the procurement of the 1730 such systems required for the machine.

In the framework of the collaboration with CNRS-IN2P3, France, the design of the short straight sections (arc) was completed. The second prototype Short Straight Section (SSS) was successfully assembled at CERN in the beginning of the year, and is now integrated in String 2, while the first prototype has undergone a second campaign of measurements before its preparation for String 2. Both prototypes have successfully confirmed the SSS design, the assembly procedure and tooling retained, and shown the expected performances. The procurement of the parts necessary for the assembly of the third prototype (SSS5) early in 2001 has been done. In parallel, the conceptual design of the arc dispersion suppressors special SSS was completed and the procurement of the cryostat components integrated in the contract of the SSS Arc. Connection cryostats, the last missing machine component of the LHC dispersion suppressors filling the gap of about 12 m between the SSS in Q11 and the neighbouring cryodipoles, were conceptionally designed and will be presented in a Dispersion Suppressor Design Review in January 2001.

The design of the String 2 electrical feedbox was finalized, and the components manufactured and delivered to CERN for assembly as an addendum to the CERN–BINP collaboration agreement. Superconducting busbars were delivered by industry, and the assembly work at CERN started.

Following the adoption of the new optics version 6.2, additional layout studies for arc electrical systems were conducted. This has allowed a final optimization of the architecture of the arc electrical feedboxes (DFBA), a significant reduction in the number of current leads and of superconducting electrical cables to be routed inside the cryostat, and a consequent reduction of the number of electrical interconnections between cryomagnets. Conceptual studies of the final machine DFBAs were started in collaboration with BINP under a separate ad hoc addendum to the agreement. A conceptual design review is planned in March 2001, followed by a detailed design in collaboration with BINP.

The collaboration with CAT (India) for the development and manufacture of cryostat positioning jacks entered its production phase. A pre-series of 36 pieces made in India, to be used in String 2, was commissioned at CERN.

The technologies and procedures to perform the interconnections of the LHC cryomagnets were further developed and optimized. A design review of the LHC arc interconnections was organized in April 2000. The engineering file of the dipole–dipole interconnection was sent for final approval in December. The next standard interconnection files will be sent for approval at the beginning of 2001.

The components necessary for String 2 interconnections were defined and ordered. The drawings of the String 2 interconnections were finalized. The first interconnection between a short straight section and a dipole of String 2 was performed at the end of the year. The next ones will follow at the beginning of 2001.

The technologies were validated on a full-scale interconnection model and during the first interconnection of String 2. Inductive soldering and ultrasonic welding developped by the CERN–CNRS (LAPP) collaboration were successfully applied. The design of the thermal shield and of the support of the radiative insulation was finalized and tested on a full-scale mock-up.

180 Large Hadron Collider Division Activities to be performed in surface buildings (SM18, SMA18, SMI2) to prepare cryomagnets (dipoles and SSS) for cold test and later on for installation in the LHC main ring were defined.

The definition of control and quality assurance activities was also started for all the tasks related to the interconnections.

Transport studies of the cryomagnets in the tunnel were pursued; these led to the specification of the tunnel transport vehicles, submitted to European industry.

Finally, integration studies of the machine components in the tunnel were continued, with a view to preparing the future installation.

Vacuum

PS Complex

The group continued to provide the required support for the vacuum systems of the accelerators including ISOLDE. The nTOF beam line vacuum was successfully installed and commissioned during the year. The group provides continual support for the CTF programme and for LHC-related upgrades of the vacuum systems. The reduction of impedance by eliminating harmful discontinuities in the vacuum flanges of the PSB rings was completed. As part of the design of the future LEIR ring, an experiment to measure the ion-induced desorption rate by heavy ions was installed and gave the first results shortly before the annual shutdown.

SPS

The improvement programme with the replacement of the 1200 high-voltage power supplies for ion pumps is progressing on schedule. A significant effort was made to minimize the doses that maintenance personnel receive during interventions by optimizing the procedures and layouts.

The installation of RF-shields in the pumping ports of the SPS vacuum system to reduce the transverse impedance was completed for one-sixth of the SPS. The remaining pumping ports will be equipped during the 2000/2001 shutdown by the industrial support team under a result-oriented contract. In addition the group provided support for the vacuum of the CNGS line.

Studies with LHC-type beams and high bunch intensities continued, in order to measure the effect of beam-induced multipactoring in the vacuum system. The existence of a threshold in the beam intensity required to trigger the phenomena could clearly be demonstrated.

LEP

The operation of the LEP vacuum system at the record beam energy and beam currents remained a unique challenge for the whole group. Thanks to a thorough maintenance plan, perturbations linked with the

Large Hadron Collider Division 181 degradation of the equipment due to radiation could be minimized. Any intervention had to be very carefully planned in order to avoid damaging the cables that had become very brittle because of radiation.

Last but not least, the group participated intensively in the preparations for the swift dismantling of the vacuum system and it is planned that maximum use of LEP vacuum components will be made for the LHC. A database was created together with the responsible persons from SL Division to satisfy the traceability required by the French INB regulations.

LHC Project

Vacuum components for the two SPS-to-LHC beam transfer lines are being built at BINP Novosibirsk and the first chambers have arrived at CERN and were successfully tested.

The design of the beam screen for the main ring vacuum system was finalized. Insertion tests of a beam screen into the cold bore showed that bronze-coated sliding rings are required in order to limit the required force and to avoid damage on both the screen and the cold bore. The validation of this concept in terms of heat load to the 1.9 K cold bore was completed in collaboration with the ECR group. The final specifications and the call for tender for the series production were issued and a contract was awarded in December 2000.

A major redesign of the interconnect assembly of the vacuum beam vacuum lines between cryostats led to a significant simplification, reviewed and approved in spring 2000. A collaboration agreement was signed with BINP at Novosibirsk for the fabrication of most of the components for the interconnects. The first prototypes will be available for installation into String 2.

All equipment required for String 2 has been manufactured and is ready for assembly. Deformation tests of the beam screen during a quench were made, demonstrating that the beam screen is not only deformed by the strong eddy currents, but is also pushed towards the cold bore. String 2 will be equipped with measurement devices in order to verify the various hypotheses leading to this displacement.

The design of the vacuum system for the long straight sections according to the version 6.2 optics is being studied in collaboration with other groups concerned. The search for a cryosorbing material that will be required for the part of LHC where the cold bore is at 4.5 K is ongoing. Significant progress was made in the definition of the vacuum instrumentation required for the beam and insulation vacua of the arcs. Prototype mobile pumping stations that can be fitted below the cryostat have been built. A test programme was launched in collaboration with the University of Magdeburg in order to define a reliable operating mode for the gauges used in the insulation vacuum.

The engineering design review of the TAS/TAN absorbers adjacent to the experiments took place, leading to a significant change in the proposed vacuum chamber of the TAN. For the vacuum chambers for the experiments, a review validated the design of the ATLAS and CMS vacuum systems and the major development projects for the experimental vacuum systems are close to completion. A full-scale 40 m prototype of the ATLAS vacuum chamber was assembled and will be used to make tests with the sputter- deposited Non-Evaporable Getter (NEG) films developed at CERN. Damping measurements with various materials that could be used for the supports of the experimental vacuum chambers are ongoing.

182 Large Hadron Collider Division Measurements were continued to study the non fully understood dose dependence of the secondary electron yield. The influence of the residual gas composition was investigated and it was found that a large change in the partial pressure of carbon-containing gases (e.g. CO and CH4) does not influence the rate of decrease of the secondary electron yield. In parallel, a measuring system was prepared for the remote measurement of the secondary electron yield in the SPS accelerator. This system will be installed during the 2000/2001 shutdown.

Towards the end of 1999 the COLDEX cryostat was installed for the first time in the EPA ring and the vacuum performance of a cryogenic vacuum system in the presence of circulating electrons or positrons was studied. In 2000 COLDEX was re-installed on the external beam line and gas desorption studies of co- laminate copper with saw-tooth structure were performed. Throughout this period, the effect of photon and electron scrubbing on the secondary electron yield of copper was measured on another external photon beam line under conditions closely simulating the LHC. These measurements provide valuable input for the expected pressures in LHC and are used to check the predictive power of simulation.

Collaborations with other institutes include gas desorption measurements which were made on proposed liners (passively cooled beam screens) for the LHC inner triplets on the VEPP2 machine at BINP, Novosibirsk. Measurements are ongoing at the same institute to study the dynamic vacuum performance of sputter-deposited NEG films developed at CERN. A closed-cycle cryostat/manipulator system was commissioned at CERN, in collaboration with INFN, for measurements of electron emission from surfaces at cryogenic temperatures

Industrial Automation and Supervision

The compressor station for the 18 kW cryoplant in P1.8 was successfully put into operation with the latest ABB equipment. The unified project for cryogenics controls of the LHC machine and experiment magnets was tendered and awarded and the design work by the selected firm has started.

A collaboration in the domain of supervision was set up with India within the general cooperation agreement. The first versions of the programs for the supervision of String 2 have been commissioned successfully.

The supervision system for the ATLAS barrel toroid prototype B0 was installed for the initial tests on a small-scale model B00.

The control equipment for six magnetic measurement systems and three quench recording systems to test corrector magnets in industry were delivered. A first version of the Test Master program that will orchestrate the test benches was commissioned. A preliminary version of a program for automated geometric measurements of LHC dipoles, using Leica Geosystems equipment, was delivered. The control equipment for the Strand Magnetization Measurement system in Bldg. 163 was fully commissioned.

Both the industrial Profibus DP and WorldFip interfaces were qualified in a radioactive environment up to 950 Gy. The possibility of synchronizing LHC equipment with a resolution of 10 µs using the industrial

Large Hadron Collider Division 183 WorldFip fieldbus was demonstrated. The transmission of date and time with a resolution of 1 ms also proved to be possible, using the same industrial fieldbus.

184 Large Hadron Collider Division Proton Synchrotron Division

Introduction

Following the celebration of the 40th anniversary of the PS at the end of 1999, the synchrotron this year entered its fifth decade of operation as CERN’s workhorse accelerator. The Division was once again fully occupied supplying its usual multitude of beams to the users, nevertheless finding time to work on other exciting subjects not directly linked to today’s beams, and including essential R&D aimed at the very long- term future of CERN. Nowhere else in CERN does one find such a diversity of topics being studied and machines being operated, which is what makes the Division so attractive. In April the ISOLDE technical team was welcomed into the Division, it having been decided by the CERN management that PS would be a more logical home for ISOLDE operation and development than its former home, EP Division. Then at the end of the year a group of RF experts from SL Division was also welcomed into the Division. Since it was no longer necessary to coax the best performance from LEP’s superconducting cavities after the closure of that machine, this team will become the nucleus for the construction of the new CTF3 test facility. The highlights of the year with regard to beams were the commissioning of the Antiproton Decelerator (AD) and the start-up of the neutron Time-Of-Flight (nTOF) facility. Both had been eagerly awaited by the physicists, who obtained exactly what they were expecting, although perhaps with just a slight delay. The year also saw the end of a decade of electrons/positrons in the PS for LEP, and the best run ever for heavy ions. This latter run was scheduled originally as the last, but it has now been agreed that ions will come back again in 2002/3, and of course later for the LHC. Work continued on improving the proton beam needed in the future by the LHC, and during this time a new intensity record was established for protons in the PS, and extracted from it. In summary, the year 2000 was an excellent one for the PS and for the Division.

Operation

Operating statistics for the different particle beams in the PS Complex in 2000 are presented in the tables below.

Proton Synchrotron Division 185 Operational statistics for lepton operation in 2000

Total number of hours scheduled for lepton operation, including expt. areas 6787 h Total number of hours achieved for lepton operation 6573 h Hours scheduled for lepton production for SPS/LEP, including setting up in PS 5242 h Hours achieved for lepton production for SPS/LEP 5041 h Electrons supplied to SPS/LEP 1.50 × 1017 Positrons supplied to SPS/LEP 1.38 × 1017

Operational statistics for proton operation in 2000

Total number of hours scheduled for proton operation 6477 h Hours scheduled for setting-up and machine development 441 h Hours scheduled for proton production for SPS 4038 h Hours achieved for proton production for SPS 3832 h Protons produced for SPS (at PSB extraction) 1.76 × 1019 Protons produced for SPS (at PS extraction) 1.59 × 1019 Protons for machine studies (at PSB extraction) 1.99 × 1018 Protons for AD (at PSB extraction) 2.62 × 1018 Protons for East Hall test beams (at PSB extraction) 7.74 × 1017 Hours scheduled for ISOLDE operation 3224 h Hours achieved for ISOLDE operation 3136 h Protons supplied by PSB for ISOLDE operation 8.73 × 1019

Operational statistics for Pb-ion operation in 2000

Hours scheduled for ion production for SPS 1184 h Hours achieved for ion production for SPS 1138 h Total charges of Pb53+ ions for SPS (at PSB extraction) 1.91 × 1016 Total charges of Pb53+ ions for SPS (at PS extraction) 1.4 × 1016

Operational statistics for AD operation in 2000

Hours scheduled for AD operation for physics 1482 h Hours achieved for AD operation for physics 1272 h

The Proton Run from March to September

The PS Complex started up at the beginning of March as usual, following the annual shutdown. The LPI machine was the first into action, but the proton Linac 2, the PS Booster and the PS itself were not far behind. Leptons were injected into the PS on 13 March with the protons following soon after. However, it quickly became apparent that there were some timing or synchronization difficulties affecting all machines. These problems were soon traced to an unforeseen instability in the TG8 timing units, which had been modified during the shutdown; the PS Complex has about 250 of them. When laboratory tests revealed that the problem could not be resolved easily, it was decided to go back to the old hardware/software configuration for each of

186 Proton Synchrotron Division the 250 units. Thanks to a big effort from the Controls group this change was made in less than a week, and the delivery of beam to users was not delayed.

LEP began operation on 3 April, and the East Hall beams were delivered as planned a week later. ISOLDE was also scheduled to begin operation then, and for ISOLDE this start-up was an important one as it was their first as part of PS Division. All went as planned and the PSB beams at 1.0 and 1.4 GeV, with nominal intensity up to 3 × 1013 protons/pulse, were sent to the ISOLDE target by mid-April. ISOLDE started by using the GPS target station, but one of the big priorities for the first half of 2000 was to complete the commissioning of the second separator (the HRS). This is important if 400 shifts of beam time are to be delivered to the ISOLDE users per year, as promised. This important milestone was passed at the end of May when the first scheduled HRS physics run took place.

The SPS proton physics programme was scheduled to start a week after Easter, but this did not mean that the SPS was idle until then. The PS had to supply a number of specialized Machine Development (MD) beams to the SPS machine physicists as part of the preparation of the SPS for LHC. On 2 May, the SPS began fixed- target physics operation with protons. This operation normally uses the standard five-turn proton extraction at 14 GeV from the PS. However this year, the SPS scheduled a two-week physics run to test some components of LHC detectors. These tests required the SPS to extract beam at 450 GeV, with the LHC-style 25 ns bunch spacing. As this bunch spacing is established in the PS, it was decided to perform this test run using a test version of the LHC beam in the PS, instead of the standard SPS proton beam. This mode of operation was extremely successful and will probably be repeated for similar runs in the future.

AD commissioning started on time although there had been a serious vacuum leak on a stochastic cooling kicker, and some alignment and vacuum problems with the electron cooler. However, this did not stop the AD team making excellent progress, and the goal of decelerating antiprotons to 100 MeV/c using both stochastic and electron cooling was successfully achieved by July. The AD requires two beams from the PS. First the machine is set up using 3.5 GeV/c protons, which are injected in the ‘wrong’ direction around the AD machine (i.e. they circulate anticlockwise). This has the advantage that the AD can be optimized for deceleration with a relatively intense proton beam rather than with low-intensity antiprotons. However, the beam cooling systems do not work in this mode. Therefore, the transverse emittance of the 3.5 GeV beam has to be very delicately controlled in the PSB and the PS, to allow subsequent deceleration in the AD. Then, to produce antiprotons, the AD needs a high-intensity 26 GeV proton beam incident on the antiproton production target. This beam is produced by injecting four PSB bunches into half of the PS circumference and then compressing them into a quarter of the circumference, just before ejection from the PS. This new scheme was made operational during the PS start-up and 1.5 × 1013 protons at 26 GeV were available for antiproton production for AD right from the start.

Every 12 weeks or so, the PS main power supply needs some regular maintenance because it is rotating machinery (and is now more than 30 years old). A 10-hour technical stop was scheduled for 7 June, in the shadow of which other interventions were carried out, including a large amount of scheduled (and unscheduled) vacuum work on Linac 2, the PSB and the PS. All the PS Complex water stations were also stopped for routine maintenance and inspection. In spite of the large amount of work carried out, all the beams were back again by early evening. For the PS, this was simply a continuation of what had been already operational: protons for SPS, leptons for SPS/LEP, slow extracted beams for DIRAC and the other East Hall experiments, the AD production beam, and a number of MD beams for both PS and SPS studies. At the

Proton Synchrotron Division 187 Booster, the ISOLDE programme at the GPS station was in full swing and, throughout June and July, the commissioning tests of the HRS continued.

During June, a lot of effort was put into completing the commissioning of the AD machine, in order to meet the re-scheduled deadline for starting AD physics on 10 July. By 14 July, the ASACUSA team was able to announce that it had made ‘a complete scan of a 597 nm resonance’. This was done with only 10 AD antiproton shots in a single afternoon. During the preliminary AD test run in December 1999, a similar scan had taken 24 hours. However, there was still a lot of work to be done, and all through the summer the small AD team shared the beam time with the physics experiments to complete the AD commissioning phase. This sharing of beam time between experimental physics and the machine studies programme was very successful, and by the end of the year the AD was running with over 85% antiproton beam availability for the experiments out of the 110 scheduled hours each week. Although the AD cycle is still a factor of two longer than planned, the decelerated intensity is more than double the design intensity, which allows the AD users to profit fully from this unique machine.

By August the SPS machine development experts were ready to begin studying the ‘full’ LHC beam in their machine. There were some concerns at the PS about the long 26 GeV flat-top on the LHC cycle, which means that the r.m.s. current in the ‘8-loop’ pole-face winding exceeds the maximum allowed value if there are too many of these cycles in a single PS supercycle. Fortunately it was possible to increase the limit on this r.m.s current just enough to allow the required three consecutive LHC cycles. However this is still a severe limitation, and modifications will have to be made in the future. Another major development on the LHC beam was the demonstration by the RF specialists of triple bunch-splitting in the PS. We have grown accustomed to the complex RF gymnastics in the PS, but this is probably the most complex yet! By injecting six PSB bunches into the PS and then splitting them successively into three bunches and then two and two again, we obtain 72 bunches with the correct 25 ns LHC bunch spacing. This scheme has the advantage that the longitudinal beam emittance is kept very closely under control and it is much easier to give the SPS the correct longitudinal emittance. This ‘new’ LHC beam was successfully used by the SPS for their long MD at the beginning of November and has become the ‘standard LHC beam’. The scheme is so flexible that it was possible to supply the SPS with another new beam having 50 nsec bunch spacing, with less than three days’ notice. It is interesting to note that this reduction in longitudinal emittance for the SPS has given indications that the LHC beam in the PS might also be affected by trapped electrons.

The Pb-Ion Run from September till the End of the Year

After a three-day stop from 11 to 13 September, the PS Complex started supplying Pb ions to the SPS for setting up, and then for ion physics from 18 September, in parallel with the other users, in particular LEP. This run lasted until 27 November, and was the best ion run the SPS users have ever had, thanks, amongst other things, to the very stable beam supplied by Linac 3, PSB and PS.

After a much-discussed one-month extension, LEP took its last beams from the PS early in the morning of 2 November. This ended a period of more than 11 years of lepton acceleration in the PS. LPI had delivered its electrons with the high efficiency and quality we have come to expect until the very last moment of LEP operation on 2 November. The end of LEP, however, did not mean that the LPI could take a rest. Immediately after the LEP stop, LPI was put to use supplying electron beams for a number of experiments which are testing LHC equipment using the LIL electron beam and the synchrotron radiation emitted from EPA. This run ended

188 Proton Synchrotron Division on 21 December. Originally this should have been the end of LPI operation, but the LEP extension meant that LPI has to be put back into service again for six weeks at the beginning of 2001 to complete these measurements. The conversion of LPI to become the CTF3 facility can only begin after that.

In November, after a number of delays to ensure that the radiation safety criteria were correctly met, the first operation of the nTOF facility began. Initially this zone was supplied with low-intensity pulses (less than 4 × 1011 protons) at 20 GeV, which are accelerated on the same cycle as the normal East Hall beam. However, at the very end of the run, a full-intensity test of the facility was made with a few hours of operation at 7 × 1012 protons/pulse, using dedicated 20 GeV cycles. Following this run, the PS was shut down but the Booster continued for several days, operating at 600 MeV for some dedicated ISOLDE tests. This mode of operation ended on 7 December.

Amidst all this activity on new beams, there was still time to improve the existing beams. Thanks to a number of improvements in the PSB and a lot of painstaking work by the PSB team, the Booster was able to supply over 3.3 × 1013 protons/pulse regularly to ISOLDE. The PS also took advantage of this increased intensity, and in August a new all-time intensity record was set in the PS with 3.5 × 1013 protons injected and 3.305 × 1013 accelerated and ejected at 14 GeV, a full 6% increase over the previous record dating from 1997.

Lepton Operation

The LEP Pre-Injector (LPI) provided beam to PS, SPS, LEP and to the LPI experimental areas for 7032 hours in 2000. Most of the time (5544 hours) was dedicated to providing beam for LEP physics, for which the LPI availability remained very high, greater than 98%. Owing to the great flexibility of the pre- injector, synchrotron light from the accumulator ring was also used, in parallel with the LEP fillings, to study photo-desorption effects in LHC components. Beam was also sent to the LEA area simultaneously with, and completely in the shadow of LEP, thus permitting further progress on technical studies for LHC detectors without bothering the LEP users. Altogether 4992 hours of operation were recorded for the synchrotron light facilities, 960 hours for the LEA area, and 72 hours with the HSE beamline. Intensive machine studies were performed during the year with the LPI to investigate the performance of the linac (LIL) and of the Electron Positron Accumulator (EPA), both of which will be transformed and rearranged into the CLIC Test Facility (CTF3) in 2001. Because of the extension of one month given to the LEP physics programme, the series of studies for LHC using the LIL areas was not completed, and it will therefore be necessary to run LIL and EPA for some weeks next year in order to complete the measurements.

Proton Operation

Proton operation in the complex went smoothly in 2000, and as mentioned above, new record intensities in the PS were obtained. An important improvement was made to the transfer line between Booster and PS in that the yokes of the trajectory-correcting dipoles were changed from solid to laminated. This, together with a change of their supplies meant that the trajectories can now be corrected from pulse to pulse (PPM), which allows a much better control over the beam at the entrance to the PS and helps with the extremely tight emittance tolerances required by the LHC.

Proton Synchrotron Division 189 An interesting new feature was a special run made after the end of the normal physics schedule, when a dedicated period of operation of the Booster was given over to ISOLDE tests using a 600 MeV extracted proton beam instead of the normal 1 or 1.4 GeV. The aim was to compare the yields of particular isotopes from one target unit using different proton energies; such a direct comparison had never been made before. To do it, however, required establishing the extraction and transport parameters for the Booster and the transfer line to ISOLDE. All went extremely smoothly, and the results showed that in general ISOLDE has nothing to gain by using a 600 MeV beam, even for species close to stability. Another interesting study made with the PSB concerned the possibility to pulse it faster, twice as fast in fact, at 0.6 s; such a pulse rate might become interesting in later years when the LHC demands on the supply of protons become high.

Pb-Ion Operation

Although it was not needed for delivering beam to the ion experiments until much later in the year, the heavy-ion Electron Cyclotron Resonance ion source, ECR4, started up at the end of March. The aim was to study light ion yields with a new, moveable extraction geometry. Ions of helium, oxygen and argon were extracted and accelerated in the RFQ. But the RFQ can only accelerate ions with an incident energy of 2.5 keV/u, so the extraction voltage from the source is not optimal for these light ions, hence the interest in being able to adjust the extraction gap externally without breaking the vacuum. A prototype extraction was designed using a simplified electrode (easier to machine) but early tests with high voltage gave severe discharge problems. The extraction is embedded in the solenoidal fringe field of the source, and a standard extraction puller electrode works perfectly under these conditions, so it was a mystery why the new geometry did not work. However, before the problem could be solved, the Pb-ion running period had to be prepared.

The operational period started in mid-September. Unlike 1999, the start-up proved to be very smooth and the ECRIS reached its normal operating conditions in about 24 hours. The source was again adjusted to favour stability over absolute intensity, and ran for just over 40 days providing a virtually constant current of 22 to 23 mA. At this point it proved necessary to reload the source with lead for the remaining eight days of the run. During the whole ion run the beam availability out of the linac was over 99%. In the PSB and the PS, operation for the ion beams has become virtually a routine procedure after an initial check by passing the ion beam through the complex during an MD session. The PSB still continues to suffer from transmission problems due to machine vacuum conditions, a situation exacerbated by the presence of a large percentage of high-intensity ISOLDE pulses in the supercycle. This phenomenon hid a vacuum leak in one PSB ring for some time until a leaking valve was discovered and steps were taken to reduce its impact on the beam.

After the physics run, a final attempt was made to solve the problems with the adjustable extraction geometry by adding a piece to the puller, to simulate a collar on the normal puller. The behaviour of this extraction was now comparable to the standard one, to the relief of all concerned, but it is not yet understood why a small addition in a virtually field-free region should have such a major effect. Bearing in mind the future use of LEIR as an accumulator for ions for LHC, the Linac 3 ion beam was used to test ion-induced desorption from a variety of pre-treated vacuum chambers. Pb27+ and Pb54+ ions were used, with repetition rates varying from one pulse every 1.2 s to 1 pulse every 16.8 s.

190 Proton Synchrotron Division Experimental Areas Operation

East Hall

The East Hall was very busy throughout the year, with secondary beams delivered for LHC tests to 33 different teams sharing the four beam lines. Irradiations of detector components were also provided for a large fraction of the year in the two irradation areas now available in the Hall: one of these provides 24 GeV/c protons in t7, and another provides parasitic neutrons behind the DIRAC beam dump.

But the Hall is used not only for tests. There are now two fully-fledged experiments taking data. One is the DIRAC experiment (PS212) which measures the lifetime of π+π– atoms as a stringent test of medium-range QCD. The other is the newly-approved HARP experiment (PS214) which had a one-month technical run in the autumn. This experiment will use the t9 area to its full potential throughout 2001 in order to get precise measurements of the production cross-section of pions from protons on various target materials, as a function of the incident proton energy. These results are eagerly awaited since they affect how a Neutrino Factory may be designed.

AD Hall

The three AD experiments ASACUSA, ATHENA and ATRAP were all installed last year. This year saw the completion of the set-ups and the installation of the RFQD in the ASACUSA area. For the future, the DEM line will be prepared as a zone where machine development measurements may be made, and perhaps very small, temporary experiments may be accommodated.

ISOLDE Hall

The ISOLDE experimental Hall is full, and one can hardly see where any new apparatus could be installed. Nevertheless the REX experiment build-up continues, although it is nearing completion. As part of the ISOLDE Consolidation effort next year, the ISOLDE experimental Hall will be equipped with an access control system, and the main door through which equipment enters will become double such that cleanliness in the Hall can be maintained.

LEA (LIL Experimental Area)

LIL provides an electron beam of 500 MeV to the LEA zone whose intensity, pulse duration and repetition rate can be adjusted according to the user’s requests. An LHC detector group (CMS) made use of the beam for 960 h in parallel with the beam to LEP. The group continued previous work with electrons to measure on-line the damage created by radiation in quartz fibres. Successful runs gave very good results for 0.3 mm and 0.4 mm core diameter quartz fibres. The hope is to be able to select the best type of fibre for the CMS forward calorimeter which is very sensitive to the electromagnetic component of hadronic showers.

Proton Synchrotron Division 191 SLF (Synchrotron Light Facility)

The two synchrotron light facilities (SLF) on EPA ran for 4992 h during the year. One of them (SLF92) was used by the COLDEX experiment. The experimental results confirmed that the gas desorption induced by synchrotron radiation from surfaces kept at 4 K is acceptable for the LHC. A new beam screen for the LHC composed of co-laminated copper/steel with a sawtooth profile was developed. The gas desorption reduction in the presence of photons was confirmed. The other line (SLF42) was used by the photon-scrubbing experiment. Studies were made on copper/steel co-laminated material at room temperature for the straight sections around LHC detectors. Photoelectron yield measurements were performed together with forward reflectivity measurements. Photon and electron scrubbing studies were also continued. All these parameters are crucial for the LHC machine.

HSE line

As last year, the EPA extraction line (HSE) was used to continue studies on RF shielding and skin effects for the LHC. RF shielding exists for finite cavities when the inside of the chamber is completely coated with 2 µm of titanium. However the ceramic chambers foreseen for LHC extraction kickers will use stripes. Further studies were requested with the HSE line. One ceramic chamber was coated on the inside and a second one was not; a magnetic probe (1 GHz) monitored both. First results showed that with one stripe only, the current does not use the path with the smallest resistance.

ISOLDE

Operation

Responsibility for the operation, maintenance, and development of ISOLDE, the isotope separator on-line facility, was transferred to PS Division from EP on 1 April 2000. A new section was created in the PP group for the ion-source and target unit production, while the remaining staff was integrated in other PS groups. In this new organization the OP group is responsible for ISOLDE operation. The long-term aim is that the facility will operate like any other PS machine from the main control room, with support from the PS expert groups as necessary. This solution will take time to implement and only a first step was taken towards it in 2000 with the introduction of some limited support from the PS Booster operators to the ISOLDE engineers in charge (EICs). Nevertheless, this year a record number of protons (a total of 8.1 × 1019) at different energies (0.6, 1.0 and 1.4 GeV) were sent to the separators, a record number of ISOLDE shifts (both for physics and for target developments) were achieved, and a record number of interventions in radioactive areas were made.

The goal of the operational year 2000 was to run a full physics programme with 300 shifts on the General Purpose Separator (GPS) and to commission the High Resolution Separator (HRS) in low resolution mode for 100 shifts. In reality, ISOLDE delivered 345 shifts of which 296 were pure physics shifts and 49 were for machine development and target tests with radioactive beam. The GPS delivered 295 shifts and the HRS 50 shifts, which is only half the expected amount. The reason for this was a malfunctioning front-end which could not be repaired during the on-going physics run. In the user community, 41 experiments were ready to take up to 492 shifts at the beginning of last year. The physics co-ordinator managed to distribute the

192 Proton Synchrotron Division 345 shifts available to 38 of these experiments, an excellent achievement. For 2001 there are experiments waiting for 600 shifts, a normal amount of backlog which will give the physics co-ordinator sufficient freedom to distribute the planned 400 shifts efficiently.

A total of 37 ISOLDE target and ion source units was irradiated during the year, 25 on the GPS and 12 on the HRS. This permitted a record number of physics shifts to be achieved. This success was due to the extension of the run as a single user during the 600 MeV test, to the absence of ‘critical day’ interruptions, and to the use for the first time of PPM mode between the two separators.

Targets

Altogether 29 targets were assembled and tested off-line in 2000. On average over the last five years, more than 11 physics shifts were obtained for each target unit produced. In 2001, with the arrival of the second technician in charge of target assembly, the goal of 40 targets/year will be within reach. The production of targets in recent years is summarized in Fig. 1.

30 20 10 0 1990 1992 1994 1996 1998 2000 2002

Fig. 1: Number of target units produced as a function of the year.

During 2000, 35 target and ion-source units were put on the separators, and the 11 different target materials used were oxides (titanium, calcium, zirconium, cerium and thorium), carbides (lanthanum and uranium), molten metals (lead and tin), metal foils (niobium and tantalum). The 2 µm Ta-foil targets developed in 1999 were used twice in very successful runs to produce neutron-rich beryllium and lithium isotopes. The ISOLDE Resonant Ionization Laser Ion Source (RILIS) was used in conjunction with tungsten and niobium high-temperature cavities for the ionization of beryllium, gallium, tin, indium, thallium and lead isotopes. The ion-sources of the units used on-line are listed in the table below.

Ion sources used during 2000

Number of units Ion source Transfer line

11 W-surface 5 Nb-surface 3 Plasma MK3 Temperature-controlled 4 Plasma MK5 High temperature 14 Plasma MK7 Cooled

Proton Synchrotron Division 193 Out of the 11 target materials listed, cerium and thorium oxides were synthesized and tested for the first time. Fission of thorium and uranium can be induced in many ways (by neutrons, photons or charged particles). Prototypes were designed to test fast-neutron-induced fission on thorium oxide and uranium carbide targets. The high-energy proton-to-neutron converter consisted of 10–20 cm long, 10 mm diameter tantalum or tungsten rods bombarded with 1 or 1.4 GeV protons. The design allows one to direct the proton beam either onto the target, or onto the nearby converter. For the first time, the fast neutrons and high-energy proton production cross-sections of neutron-rich isotopes of xenon, krypton and caesium were directly compared. It turns out that the evolution of the cross-section for very neutron-rich isotopes is in first order independent of the mechanism inducing the fission. As the converters are much more robust towards thermal shocks than ISOLDE targets, higher proton beam power could be handled by them in the future. The development of target materials and ion-sources was greatly helped by contributions from the EURISOL project members.

Front-ends

ISOLDE front-ends are designed as disposable items with a planned lifetime of the order of five years. Currently there are three front-ends, but the one on the HRS (No. 2) is unreliable and will be removed in the next shutdown and sent for disposal. There will then be no spare. The first of a new generation of front-ends is under construction but it will not be ready until the beginning of 2002, so that we will be forced to run in 2001 with the existing front-ends. The way the target couples to the front-end is shown in Fig. 2.

Grounded x-y-z movable extraction electrode –60 kV Vacuum vessel Electrostatic quadrupole triplet

Target Ion source

Turbo molecular pumps (2 × 1000 l/min)

Fig. 2: An ISOLDE target and ion-source unit with the front-end.

The extraction electrode x,y,z movement is the only moving part in the vacuum chamber of the ISOLDE front-end. Its task is to adapt the beam optics to the different ion source characteristics and to cope with small misalignments. The cage of one of the ball bearings of the z-positioning screw broke on front-end No. 2 but

194 Proton Synchrotron Division could be repaired after two years of radioactive cooling. This operation required dismantling in the ventilated hot cell. Over 6 man-months and 10 mS integrated dose were needed to successfully replace the faulty ball bearing. Sadly, shortly after the first real target was irradiated when it was back in service, uncontrolled sparking degraded the titanium tip of the extraction electrode and caused increased friction in the movement mechanism. The friction torque was larger than that of the clutch, thus forcing us to replace it by a direct connection. This front-end then worked, but could not be considered reliable.

Consolidation Project

The 10 years since the move of ISOLDE to the Booster, together with recent budget constrains, has led to a situation where a consolidation programme is urgently needed to guarantee the future of the facility. Furthermore, the European legislation for radiation safety has recently been revised. To bring the level of radiation safety at ISOLDE in line with this new legislation, important investments have to be made. A consolidation plan stretching over three years has been established for the facility. It will be run as a project involving two main activities. The first addresses the radiation safety issues and involves an extension and improvement of the present buildings; this is to ensure that the target area and a new workshop extension can be classified as a class A radioactive laboratory, and that the experimental hall can be upgraded to a class C laboratory. The second activity is the technical consolidation, involving among other things the building of a new spare front-end, the high-resolution mode of the HRS, renovation of target manufacturing facilities, and improvements of the radioactive beam quality. The project will be financed partly by the ISOLDE collaboration.

nTOF

At the beginning of November, a beam of 20 GeV/c protons was delivered for the first time to the target of the nTOF experiment (neutron Time Of Flight) in the TT2A tunnel. The effort spent preparing this beam beforehand bore fruit because the requested intensity was quickly obtained (a few 1011 protons) in the required 25 ns bunches. This low-intensity beam is practically ‘free’ because it is produced during the same PS magnetic cycle as that which supplies the normal East Hall beam; in fact it comes from the beam accelerated in one of the Booster cycles that is unused during a normal East Hall PS cycle. At the same time, the designers of the neutron-producing Pb target were able to verify that the number of neutrons emitted, and their energy spectrum, were as expected.

Following this milestone, efforts concentrated on producing a beam of the same energy but of much higher intensity for nTOF, up to 7 × 1012 protons in bunches of 25 ns. This beam, which is at the limit of what the PS can produce, requires very delicate adjustments to the PS, particularly at low energy where there are strong space-charge effects, and at transition where there is beam break-up instability. However, the beam was produced, transported, and measured thanks to the active collaboration of almost all the PS groups. It was then used, right at the end of the year, to measure the heating effects in the Pb target, which had been a cause for concern. Both the new proton beams will be used in 2001 to supply the many users eagerly waiting to start their neutron measurements in the nTOF experimental area, about 200 m downstream of the production target.

Proton Synchrotron Division 195 Antiproton Programme

The AD project reached its successful conclusion and was commissioned and turned over to the users as a going concern. Beginning in April, soon after the PS complex start-up, the AD set out on a long and intense period of machine development, whose goal was to improve the performance obtained in 1999 and reach the design specifications in time for the start of the physics programme foreseen for 10 July. The list of areas needing improvement was quite long: the ring optics and acceptance, the antiproton deceleration efficiency, cooling at several beam energies, re-bunching prior to ejection at 100 MeV/c, set-up of the ejection lines, and shortening of the AD cycle.

After extensive work on the ring optics at both high and low energies which resulted in higher transverse acceptances as well as a better understanding of the optics at low energy, a regular antiproton deceleration cycle was established. The stochastic cooling system, which already worked satisfactorily at 3.5 GeV/c was now optimized at the 2 GeV/c flat-top and as a result, the final beam emittances were then well below the design values. Electron cooling improvements yielded beam emittances at 300 MeV/c close to the design values. By mid-June the electron cooling started to work satisfactorily at the lowest flat-top, and beam emittances after cooling approached the design specifications. This was the first time in the history of the AD that beam cooling had worked at 100 MeV/c. By the end of June, the first re-bunched beams could be ejected after further work on the first harmonic RF-system.

The first antiproton beams of the new millennium for physics were delivered on 10 July. First to receive the 100 MeV/c antiprotons were the ATRAP and ASACUSA Collaborations, followed some two weeks later by the ATHENA team. After that, each Collaboration ran with exclusive beam time for a period of two to eight hours before passing on to the next team. The normal running schedule was from Monday morning to Friday evening, but in order to increase the efficiency and reduce the downtime, the ACR crew effort was increased from October onwards, when nights were introduced on the shift rota. In September, a short shutdown was made to allow the installation of the RFQD which is part of the ASACUSA experiment. This was followed by two weeks of dedicated AD machine development time.

Continuous evolution towards the design goals was maintained by programming machine development periods in parallel with the physics; this was done on a weekly basis until the AD shutdown on 30 November. The characteristics of the extracted beam were gradually improved over this period. Areas of improvement included beam intensity and stability, orbit stability, extracted bunch length and time stability, electron cooling, and the AD cycle length. Towards the end of the run, the AD regularly extracted >2× 107 antiprotons in a 330 ns long bunch every 112 seconds. Record intensity of the extracted beam at 100 MeV/c was 2.7 × 107 per bunch. Some time was also spent on studies of the ‘stacking’ mode, in which the AD accumulates several batches of antiprotons at 3.5 GeV/c before deceleration and extraction. The beam availability for physics during the period from July to November was 85.9% with a total of 3540 hours logged for the whole year.

To round off a successful year, the AD went ‘live’ in November for the second time. Just as in May, the AD was again the guest star in a series of Webcasts within the framework of the ‘Live from CERN’ project. This time, the theme was ‘the antimatter factory’: a ‘mission impossible’ team of three students from the

196 Proton Synchrotron Division Geneva region was sent around CERN in search of the necessary ingredients for anti-hydrogen production. Once the mission was completed, an alien turned up in the studio looking for antimatter for his spaceship which was unfortunately out of fuel! This adventure was followed by a large audience placed in the CERN Microcosm studio, the observation tower in Tampere (Finland), the assembly hall of the University of Bari (Italy), the Exploratorium in San Francisco (USA), and in classrooms all over the world. A question-and- answer session was then held between the audience and the engineers and physicists working on the AD machine and its experiments. All the CERN participants enjoyed it and we hope the audiences did too.

RFQD

The decelerating RFQ, designated in CERN as RFQD, successfully delivered low-energy antiprotons to its ASACUSA users. The design was based entirely on calculations and was built without a prototype. Initially some discrepancies with theory appeared in the form of a much higher than expected RF power requirement, and a distorted field. However, this can be attributed to the great length of the device (3.6 m corresponding to 2.4 RF wavelengths) which makes the structure very sensitive to slight tuning variations. It also reduces the resolution of full-length simulations, because of the practical limit on the number of mesh points that can be used. The problems were solved by upgrading the RF amplifier chain to higher power, by additional copper plating, and by geometry adjustments to the 34 internal RF cells.

Fig. 3: The RFQD installed in the AD hall.

Proton Synchrotron Division 197 The RFQD was brought to full RF field at the beginning of the summer, then packed and transported to the Tandem accelerator of the University of Aarhus in Denmark, for a short period of beam tests with 5 MeV protons. This beam offered the advantage of a much higher repetition rate than available with AD, together with the possibility of using standard proton diagnostics such as Faraday cups. The tests were entirely successful, and the RFQD was immediately packed and shipped back to CERN.

After reinstallation in the AD hall (see Fig. 3), physics runs started at the beginning of November. Antiprotons, decelerated to kinetic energies of 15 keV, were routinely provided with transmissions of 50–70% of the theoretical figure and ‘publishable’ results were rapidly obtained by the physicists of the experiment ESA, part of the ASACUSA Collaboration. Precious experience with the new hardware was gained at this time, but a dedicated measurement period is foreseen immediately after the start-up in April 2001 to consolidate the project.

Diagnostics

The maintenance and operation of the numerous (~ 1000) beam measurement devices spread out along each of our accelerators and transfer lines is a permanent source of concern, in order to ensure that the operators have reliable and precise tools. This is especially true for the stringent conditions imposed by LHC beams. This year it was, in addition, necessary to finish the AD instrumentation and to equip the new nTOF facility. For this latter, the effect of the high charge in each beam bunch means that existing diagnostic equipment had to be modified. Also, with the arrival of ISOLDE in the Division, the specific nature of their instruments necessitated a review of both hardware and software issues in order to formulate a consolidation plan for 2001. As LPI will be converted into CTF3 next year, a facility with yet further new characteristics, a number of existing LPI instruments will have to be adapted and new ones created.

For AD, the problems encountered with the measurement of the closed orbit under the extreme conditions of deceleration were solved. The measurement of the beam intensity and its longitudinal properties using the new Schottky pick-ups are now available, but instrumentation for the transverse parameters of the decelerated beam are still being developed. For the tests of the RFQD with protons at Aarhus University, extremely sensitive monitors were constructed to permit digitization of the beam profiles for very low energy, low intensity beams. These helped a great deal in making the RFQD operational so rapidly.

To prepare the PS for the LHC era, efforts concentrated on the ‘fast blade’ or ‘guillotine’ monitor, which allows us to measure the distribution of transverse amplitudes of the beam. The mechanisms were installed in the Booster during the shutdown, as was the control electronics. First results were encouraging and point the way to improvements of both the software and the electro-mechanics. Mounted in one PSB ring, the monitor will be a reference for comparison with other measurements of the transverse beam properties, in particular the beamscope. Concerning the eight new fast wire scanners delivered by TRIUMF, the mechanical elements were installed in the PSB and the control electronics is being fabricated for testing early in 2001. The SEM grids in the measurement line after the Booster were replaced by a model with finer resolution so as to measure the LHC beams more precisely.

198 Proton Synchrotron Division Emittance preservation is essential along the accelerator chain for LHC, and to this end, instruments to measure the matching between the PSB and the PS are under study. In particular, the comparison in the PS between a multiturn SEM grid and a quadrupole pick-up are continuing. The results so far are in excellent agreement, which opens the way for non-destructive and permanent measurements of the transverse beam properties at injection to the PS in the LHC era. In the same way, wide-band pick-ups were placed in the transfer line from PS to SPS so as to observe the positions and intensities all along the train of 72 bunches as it goes to the LHC. Complete tests of the digitization system will be made next year. Meanwhile the development of slow current transformers for LHC continues, and comparisons between the prototypes made at CERN and commercial equipment are being made.

Accelerator Controls

The exploitation of the control system driving the PS Complex on a day-to-day basis is in the hands of the CO group. This includes the support to the operators of an efficient ‘on-call’ team, the continuous introduction of changes when requested by the operations crew, and the upgrading of the software and hardware components for better reliability or more suitability to the needs. This activity proved once again to have been very successful since the fault rate attributed to the controls in 2000 reached a record low level of 0.2% over the whole year. The AD machine remained the most demanding machine of the PS Complex in terms of day- to-day care and follow-up of its evolving operating conditions. The ISOLDE controls were officially integrated with the arrival of the ISOLDE technical team in April 2000, but remained under the responsibility of a few specialists because of their specificity.

Developments in 2000 were all aimed at improving the reliability and overall performance of the control system, whilst reducing the manpower and operating costs necessary to run it. On the hardware side, the network was completed with the extension of the structured network cabling to both ISOLDE and LPI. The replacement of the VME front-end crate controllers with PowerPC-based units was extended to all the PS machine VME control crates. The TG8, the basic component of the PS timing system, was completely redesigned and successfully tested in operation. In addition, a project was started to deal with the introduction of industrial equipment interfaces in the PS system (PLCs, Profibus, etc). Local file servers were exchanged for Linux machines, and the controls database was installed on a new machine under IT Division responsibility. Finally, in the framework of the controls desktop migration, two consoles of the PS main control room were successfully converted to standard PC workstations running Linux, thus paving the way to a complete migration in 2001.

On the software side, the ‘middleware’ layer developed in collaboration with SL Division has been implemented, based on CORBA and MOM technologies. First tests were made successfully at the end of the year, opening the way to its installation in the PS environment in the first half of 2001. The architecture of the central sequencing system needed by PS and SPS to satisfy the LHC requirements was defined, and the implementation phase was started. Most of the existing XWindows/MOTIF applications programs were ported to Linux. Lastly, the Java programming environment was further developed using commercial tools, and the Accelerator Software Component (ASC) layer was broadened to provide applications programmers with easy and powerful program objects.

Proton Synchrotron Division 199 In order to modernize the ISOLDE control system, a new infrastructure for the front-end computers was defined which is compatible with the existing PS controls, and takes account of the wishes of the ISOLDE users. This project will be implemented in two stages in 2001 and 2002. It is based on the DSC/VME PS standard infrastructure with the addition of industrial components. The necessary know-how for the latter has to be acquired, and issues related to the integration of these units in the existing control system have to be understood. To this end, a dedicated test stand is being set up in the laboratory. In 2001 a selection of power supplies for the ion source and the lenses will be implemented, using PLCs and I/O modules distributed on a PROFIBUS fieldbus. For the CTF3 project, the realization of new controls has started on the basis of the existing LPI control infrastructure. All new equipment installed will use the same components as the other accelerators of the PS Complex.

Finally, it should be noted that the CO group has the task of providing the Division with its desktop computers. As every year, the oldest PCs were replaced, so that upgraded Pentium 133 MHz machines are now the lowest level of PS desktop computer. New public printers were installed and the video equipment in the conference rooms was renewed. As a test for the deployment of Windows 2000 (delayed by IT Division to 2001), a few machines were migrated in order to gain experience and help elaborate a procedure for the global deployment, but this was not without difficulty.

Consolidation of the PS Complex

Our consolidation efforts were particularly active in the area of power converters. For example at the Booster, new power converters for the BTP line adapted for PPM were commissioned, and preliminary studies were made of the regulation electronics of the Booster main power converter, aimed at testing the feasibility of pulsing with 0.6 s cycles at 1.4 GeV in the future. At the PS, development work for a new B-train electronics was started, as was a new gate control set for the PS main generator and control logic (using PLCs) for the rectifiers, in order to improve stability and reproducibility.

Kickers and septa were also involved in the consolidation programme. Modifications to the KFA71-79 electronics were made to permit true PPM operation for these modules, improvements were made to the PSB transfer kicker pulse flat-top to give it a < 1% ripple, and a new compact PCI-based control front-end for the ISOLDE HV target pulsers was designed and installed. The spare electrostatic septum PE.SEH 31 was installed during the shutdown, but then a new-generation electrostatic septum PE.SEH 23 was designed, constructed and built; this uses standard vacuum seals, improved vacuum equipment, and has in-vacuum bake-out lamps. The septum is ready for installation in the next shutdown. For the magnetic septa, the biggest job concerned the recuperation of the highly radioactive SMH16 which had been taken out of the PS ring in January 1999 after some laminations sheared off, blocking the gap. New coils were manufactured and installed, and the new, improved magnet is now fully tested.

Finally, our campaign to remove old cables came to its end with further work in the Booster galleries, and in several odd corners of the PS Complex. Of order 1000 cables were removed which filled four large skips, and the work represented roughly two man-years of effort.

200 Proton Synchrotron Division PS Protons for LHC

With virtually all the planned hardware already installed, the project of upgrading the PS Complex as LHC proton pre-injector is coming to an end. The last major item still in the pipeline, the closed-circuit PSB water cooling and air conditioning system, was put into operation in March 2000 and works as expected. Although the water inlet temperature of the PSB magnets eventually reached ~ 27°C during the summer season, no adverse effects on the PSB beams were observed.

A series of machine development sessions was carried out with a view to producing the ‘nominal’ LHC beam at 26 GeV/c, i.e. an intensity of 1.1 × 1011 protons/bunch, a transverse normalized r.m.s emittance ≤ 3.0 µm, a 25 ns bunch spacing, and a bunch length ≤ 4 ns (to fit into the SPS 200 MHz buckets). Already by the end of 1999, a beam with the nominal intensity and transverse emittances of ~ 2.5 µm (better than specified) was successfully produced, demonstrating that the scheme (involving two-batch filling of the PS at an increased energy of 1.4 GeV) works in the transverse plane. However, the 4 ns bunch length (involving non-adiabatic bunch manipulations based on new 40 MHz and 80 MHz cavities) could not be achieved with the nominal intensity. The problem was that the original scheme was based on a debunching–rebunching process in the PS which is plagued by longitudinal microwave instabilities leading to an uncontrolled blow-up in momentum spread, and hence to bunches with excessive length.

Although this instability may probably be tackled by a systematic effort to reduce the PS impedance (e.g. by dismantling the 114 MHz lepton cavities), a radically new way to produce the LHC proton beam in the PS was proposed. It is based on the recently invented triple-bunch splitting which was successfully demonstrated in 1999, as well as on the more conventional splitting of one bunch into two. This scheme (Fig. 4) consists of the following steps:

– the PSB provides two batches of three bunches each, filling six out of seven PS buckets (i.e. the PS RF system is tuned on harmonic 7), thus leaving a void in the PS ring;

– the six bunches are split into 18 by triple-bunch splitting which are then accelerated to 26 GeV/c;

– on the PS ejection flat-top, the 18 bunches are sliced (by two steps of double-bunch splitting), into 72 bunches 25 ns apart, with a void of 12 empty buckets. The RF harmonic is 84. Note that a 20 MHz cavity is required for generating the intermediate RF harmonic 42;

– the 72 bunches are shortened to 4 ns by means of the 40 MHz and 80 MHz systems followed by extraction, as in the old scheme. The kicker risetime is placed in the beam void, thus enabling ejection without mis-steered bunches.

In a crash programme, a prototype 20 MHz cavity was assembled using obsolete equipment, and the low- level electronics for all the splitting operations was prepared. After a series of machine studies on this new scheme, a truly nominal LHC beam, featuring the correct transverse properties as found in 1999, but with a bunch length of ~ 3.8 ns at nominal intensity, was achieved (see Fig. 5) for the first time in November 2000. This new scheme offers an unexpected fringe benefit: by omitting one or several PSB rings, bunch trains and holes of different length can be generated. Moreover, other bunch spacings (50 ns, 75 ns, 100 ns) are feasible. This additional feature proves invaluable for studying electron cloud effects in the SPS (a potentially serious problem for the LHC); these phenomena strongly depend on the bunch population, spacing, and length of bunch train which can now be varied. The only major drawback of the new scheme is that it requires ~ 15%

Proton Synchrotron Division 201 more protons per PSB bunch, with a concomitant increase of the space-charge tune shifts in both PSB and PS. This virtually excludes the production of the very-high-brilliance ‘ultimate’ beam for LHC (1.6 times the bunch intensity within the same transverse emittance) with the present systems.

PS ejection: 320 ns beam gap 72 bunches on h = 84 in 1 turn

Quadruple splitting at 25 GeV

Acceleration of 18 bunches on h = 21 Triple splitting at 1.4 GeV

PS injection: 6 (4 + 2) bunches on h = 7 in 2 batches Empty bucket

Fig. 4: The new scheme to generate the LHC beam (72 bunches, 25 ns spacing, bunch length ≤ 4 ns) without resorting to a debunching-rebunching procedure. Note that the ‘quadruple’ splitting is done in two steps of double-splitting.

Fig. 5: One of the 72 LHC bunches on the PS 26 GeV/c extraction flat-top, with a bunch length shorter than 4 ns.

202 Proton Synchrotron Division The ‘PS proton for LHC’ project finished officially at the end of 2000, but some items are still outstanding. On the hardware side, the eight PSB wire scanners provided by TRIUMF must be commissioned, and the PS transverse damper systems for both planes (to eliminate injection oscillations and damp transverse instabilities) must be purchased. In addition, in view of the recent success of the new RF filling scheme, two 20 MHz RF systems (tunable also to 13.3 MHz to allow an LHC bunch spacing of 75 ns) must be fabricated. Machine development sessions will be devoted to reducing the modulation in intensity between LHC bunches from the present ±20% to ±10%, which seems acceptable for the LHC. A bigger task, however, will be to produce the ‘initial’ beam which the LHC requires for the first years of collider running (with a luminosity of ~1033 cm–2 s–1). This beam features much smaller transverse emittances (25% of the nominal beam emittance), making the preservation of transverse emittance along the injector chain a major issue.

Ion Projects

PS Ions for LHC

A plan has been established to produce the first Pb ions in the LHC by the end of 2006. However, the main activity was to finalize the LEIR scheme for collecting the Pb ions needed by LHC, which opened the way to studies of options concerning the PS. Work on the improvement of the ECR source and on a Laser Ion Source continued in parallel. In addition, attention was paid to lighter ions, which have been requested by the ALICE experiment. Altogether six ion species have been specified in collaboration with the LHC specialists: lead, indium, krypton, argon, oxygen and helium. These ions give a reasonable cover of the periodic table, exist as (relatively) pure isotopes, are well-suited to an ECR-type source, and are acceptable for the experimenters. The intensities per bunch of the different ions that may be ‘digestible’ in the LHC have been worked out, and whereas for lead and indium they seem to be achievable, lighter ions are severely restricted by space-charge limits in the injector chain.

Now that the LEIR scheme is defined, limits in the PS have also been established and ways to improve the situation have been suggested. These include increasing the injection energy into the PS, and the use of a three-, two-, or even a one-bunch mode instead of the four-bunch scheme used for lead ions (i.e. where four bunches per PS cycle are prepared). The price to pay for the higher transfer energy is stronger septum and kicker magnets in the PS, apart from the higher demands on LEIR itself and the transfer line from LEIR to the PS. For the modes with fewer bunches, a longer filling time is required (more than 40 min per LHC-ring in the one-bunch scheme instead of 10 min for the four-bunch mode).

To avoid an intolerable emittance blow-up in the foil which converts Pb54+ to fully stripped Pb82+ after the PS, a low-beta stripping insertion in the TT2 transfer line (PS to SPS) has been designed, leading to β β π σ h ~ v = 5 m. It reduced the emittance blow-up by a factor of 4 to ~ 0.2 mm mrad (normalized, 1 emittance) compared to 0.8 π mm mrad in the present set-up used in the fixed target Pb runs, where the final emittance (about 4 π mm mrad compared to 1.5 π mm mrad for the LHC) is less critical. The beamline elements for the insertion (four extra quadrupoles and six power supplies) have to be found or ordered in 2001 if one wants to test the insertion from 2003 onwards. Emittance conservation is one of the challenges for the ions for LHC. To limit the emittance increase caused by stripping to the theoretical value of 0.2 π mm mrad, one needs a very delicate optical setting of the downstream part of TT2, which will require many long MD sessions. Hence it is essential to start this work as early as possible.

Proton Synchrotron Division 203 LEIR

The LEIR scheme was fully defined in 2000, after much discussion and analysis of the possible options. The aim was to define the scenario that will later be implemented for providing the ions that LHC will require in 2006. Different ways of accumulating the Pb ions (and also the other ions that seem now to be of interest to the experimenters) were considered. It has been agreed that the idea of moving Linac 3 to the South Hall to make for easier injection into LEIR should be abandoned. Rather, Linac 3 will stay where it is, and the part of the transfer line which is common to LEIR injection and transfer to the PS will be pulsed. A combined multiturn injection (both horizontal and vertical) will be installed in a straight section having large dispersion, while the 3-m electron cooling and the extraction will be installed in two opposite sections with zero dispersion (see Fig. 6). All the magnets, the majority of the instrumentation, and the vacuum chambers will be recuperated from LEAR. However, one of the principal problems to be solved is the quality of the vacuum required in LEIR. Tests are under way at Linac 3 of the out-gassing of vacuum chamber walls under the bombardment of Pb ions, and different surface treatments are under consideration.

E2BHN03 15 E2QFN11 E2BHN04 EJECTION, dispersion ~ 0 m E2QFN12 E3QFN01 E2QFN13 E3BHN01

10 E3QNN02

BHN10 QFN11 QFN12 QDN11 QDN13 QDN14 QDN12 KFH1214

E3QNN03 SMH1113 BHN40 E3QNN04 5 QDN42 QDN21 QFN42 QFN21

SMH42

0 SEH40

INJECTION, dispersion ~ 10 m QFN41 QFN22 –5 QDN41 QDN22

BHN30

BHN20 QDN32 QFN32 QDN34 QDN33 QFN31 QDN31 –10

ECOOLING, dispersion ~ 0 m –15 –10 –5 0 5 10

Fig. 6: The proposed LEIR layout.

204 Proton Synchrotron Division Laser Ion Source (LIS) Studies

The aim of the LIS experiment is to demonstrate that such a laser ion source can provide a reproducible ion pulse at high pulse rate, and can be an economic and reliable candidate as the source of heavy ions for LHC. The experiment is run by an international collaboration between CERN and Russian Institutes (ITEP and TRINITI). It is partly financed through the International Science and Technology Centre (ISTC) and INTAS (International Association for the promotion of co-operation with scientists from the newly independent States of the former Soviet Union).

During 2000, further progress was made towards a full-scale source, and it is anticipated that next year the full system will be tested at CERN. In TRINITI, a 95 J CO2 laser pulse was shaped to 10–15 ns length and focused to a power density of some 1013 W/cm2 on a target, thus generating an expanding plasma. Measurements show that more than 2.6 × 1010 ions of Pb25+ will be extractable from the plasma in a pulse of 5 µs, the time needed to fill one PS Booster ring. The value expected originally was only 1.4 × 1010 ions. Also in Russia, the manufacture of the 100 J laser pulse amplifier is advancing, and the commissioning of subsystems started in the autumn of 2000. The objective is to build a device that delivers more than 106 shots without intervention, at a repetition rate of 1 Hz. After pre-commissioning in Russia, this device should be delivered to CERN in the first half of 2001.

At CERN, most of the effort was put into preparatory work for integrating the new high-energy laser in the present set-up, and to convert the source for 1 Hz operation. In parallel, new plasma and ion beam diagnostic tools were tested successfully. These were a polychromator measuring X-ray spectra from the laser-generated plasma through the Bragg effect (in the framework of the INTAS collaboration), and a sapphire crystal detector allowing beam profile studies of ion currents at very low beta. Furthermore, to get a first idea of what a LIS could provide in the way of medium-heavy ions with mass around A = 110, a silver target was bombarded with our present, low-energy laser. The result was that approximately 3 × 1010 ions of Ag19+ could be delivered in a pulse of 5 µs through a standard extraction aperture.

CLIC

The CLIC Study

The Compact LInear Collider (CLIC) being studied at CERN is a facility that might be built after the LHC. It is an e+e– collider based on an RF system working at 30 GHz, and intended to reach a centre-of-mass collision energy of 3 TeV and a luminosity of 1035 cm–2 s–1. The work on this facility converged last year to a possible design which is now documented in a CERN report published in July 2000, under the title ‘A 3 TeV Linear Collider Based on CLIC Technology’ (CERN 2000–008). The principle of this technology is a two- beam scheme, where a high-current beam decelerated in a drive linac is used to provide the RF power to feed the main linac. The production of this high current involves many complex components such as a delay loop and combiner rings, and it is far from trivial. The beam of interest for the physics is then accelerated in the main linac at modest intensity, but to very high energy (1.5 TeV). Separate electron and positron main linacs fire their beams towards one another, and the beams collide at the interaction point (IP) which is where the experimental apparatus is situated, assumed to be located in the vicinity of the injection complex. At the energies proposed, the whole facility is about 40 km long. During the year, working groups on technical

Proton Synchrotron Division 205 services and engineering aspects were created, involving mainly ST and EST Divisions, to prepare a CLIC conceptual design. They cover the study of a site in the Geneva region, and of a possible layout. They also include feasibility investigations for the civil engineering, electrical power distribution, cooling, ventilation, etc. Taking into account the geological constraints, the tunnels would be on average ~ 110 m underground. So far this has resulted in two possible implementation scenarios, in which the injection systems and the IP are both assumed to be located within the existing CERN site. Meanwhile, work continued on important beam dynamics issues and on critical RF components such as the power extracting transfer structures (PETS) and the accelerating structures at 30 GHz, by using the test facility CTF2. Plans became more concrete for the successor facility, CTF3, which uses much of the LIL injector material liberated by the closure of LEP.

Positron production has been studied and the peak energy deposition density simulated. A new tracking code has been developed on the basis of the KEK code used for the B-factory. The phase space distribution of the final state, as well as the positron yield (0.3 e+ per e– and per GeV) has been obtained. A damping ring optics was designed, based on a TME arc lattice and using established optimization algorithms. In this design, the intrabeam scattering growth rates are orders of magnitude higher than the synchrotron radiation damping. In addition, the estimated growth times are about 0.6 turn at 10–9 torr for the fast beam-ion instability, and 14 turns for the electron-cloud instability. As a consequence, another option is being explored of a ring with a much larger circumference, in which radiation damping, intrabeam scattering and quantum excitation would occur almost exclusively in the long wiggler sections. For the main beam, bunch compression is needed in order to produce a bunch length of 30 µm. The drive beam generation requires that the bunch length be either stretched (to limit the coherent synchrotron radiation effects) or compressed (to optimize the power transfer to the main beam). A magnetic insertion, capable of achieving both these functions by changing only the quadrupole strength was therefore studied. As a challenge, this approach was first applied to the preliminary design of the CTF3 transfer line between the Delay Loop and the Combiner Ring. Solutions were indeed found which satisfy the geometrical constraints and allow a bunch variation of ±1.6 mm around the nominal value, with acceptable quadrupole gradient changes.

The effects of transverse wake-field in the drive beam decelerator were investigated for the four- waveguide structures. In particular, the dependence of beam stability on the frequency of the transverse mode and the length of the decelerator was simulated, to detect the amplification of any initial jitter at the other end of the decelerator. The results show that a deviation in frequency from the fundamental mode by 2% generates a large, asymmetric increase of the amplification factor between 3 on one side and 10 to 100 on the other side of the minimum. Studying the beam stability, the envelopes obtained after trajectory correction are found almost to fill the aperture at the low energy end. Remedies would be an increase of the decelerator length or an improvement of the correction algorithm. Simulations with the six-waveguide structures showed that the beam is significantly more stable in this case. Concerning the PETS, fabrication studies have advanced; with a 1 m- long PETS, power levels above 200 MW for 10 ns long pulses are expected in the test facility.

In the main linac, the control of the bunch-to-bunch energy spread requires compensation of the beam loading. A new method has been developed which consists in generating a ramp in the RF output of the PETS by modifying the time structure of the drive beam. The final pulse has a modulated bunch distribution whose density is lowest at the head of the pulse and grows towards a constant value in the core. This corresponds to a current ramp that produces a ramp in the PETS power output. A full bunch-to-bunch energy spread of less than 5 × 10–4 can be obtained, which is below the target value of 0.1%. Since high-gradient accelerating structures are the key components of the main linac, efforts focused last year on understanding their performance limitations. This was motivated by the discovery of surface damage in prototype 30 GHz

206 Proton Synchrotron Division accelerating sections tested in the past in CTF2, by reports of similar problems encountered in the X-band by the NLC study, and by re-calculation of the pulsed surface heating. Theoretical work centred on the analysis of the options available to optimize the structures, which involved extensive use of the program HFSS. In parallel, experiments were planned to determine the breakdown signatures, to study the physical process involved, and to discover the parameters that affect breakdown level. High-gradient tests have been carried out in a test stand installed in CTF2 (see below) and dedicated experiments on pulsed surface heating were carried out in the Russian National Institute of Physics. In an attempt to reduce this heating, slotted iris structures were further studied. Work on main-beam position monitors has also resumed, with the objective of extracting position signals from the accelerating structures directly.

At the interaction point (IP), the vertical spot-size increase due to synchrotron radiation in the detector solenoid limits the maximum acceptable crossing angle to 20 mrad for a 4 T solenoid field; this is also the minimum angle required. Several final-focus systems with finite dispersion across the final doublet were studied at 3 TeV but none reached the desired luminosity. Considering ionization heating and image currents, three or four locations in the final focus were found where spoilers could survive the impact of an undiluted beam, provided proper materials are used (carbon or beryllium). As a consequence of failures in the linac, the emittance may blow up by several orders of magnitude and this determines the minimum betatron amplitudes required at the collimators. Expressions for collimator wake-fields were compiled and programs for studying scattering by residual gas or thermal photons were installed. Investigations started on the design and layout of the final quadrupoles at the IP. Parameters were computed for γ-γ collisions. Vertical position displacements between the beam centres at the IP generate a loss of luminosity. To counteract this effect, related to beam jitter at the IP, fast position feedback systems have been modelled. They consist of correctors and beam position monitors located very close to each other on the same side of the IP.

CTF2 Experiments and Results

After the successful test of a string of four 30 GHz accelerating modules in 1999, the RF equipment was converted into a 30 GHz high-power test stand. For this conversion, the power extraction structure (CTS-L) was further improved and installed in the drive beam line of the first module, and a spare solenoid from LIL was mounted around it for improved beam focusing. During the year the CTS-L served as 30 GHz power source for all accelerating structure tests. It reliably delivered up to 150 MW. However, when the focusing field of the solenoid was applied, a shortening of the RF output pulse, together with an increase of the vacuum level was observed, probably due to multipactoring in the CTS-L.

The vacuum system and the instrumentation for the 30 GHz accelerating structure tests were considerably improved. Pumping and vacuum gauges are now installed upstream and downstream of the CLIC accelerating structure (CAS), in the feeding waveguide, and on the pumping chamber of the CAS itself. A bake-out at 150° C is now applied routinely and static vacuum levels in the 10–8–10–9 torr range are obtained. Wall current monitors (WCM) installed upstream and downstream of the CAS allow the measurement of dark current and of breakdown-related charge bursts. By applying time-of-flight techniques, the energy of the electrons constituting these charge bursts can be determined. Light emitted by the CAS during RF breakdowns into the beam pipe is detected with a fast photomultiplier, and first tests have been performed to measure mechanical vibrations of the CAS with accelerometers. An attempt to measure X-rays produced by dark current and/or RF breakdowns in the CAS failed, because of the strong X-ray background produced by beam halo losses of the nearby drive beam.

Proton Synchrotron Division 207 Three different CAS structures were tested. Two were disk-loaded waveguides of 28.5 cm active length and constant impedance. The main difference between these two CAS structures is the coupler design, which is the standard CTF one-port design in one case and a prototype two-port design in the other. The third structure was a 12.3 cm long planar structure built at the Technische Universität of Berlin, Germany. The single-port disk-loaded structure was limited by breakdown to a mean accelerating gradient of 60 MV/m, corresponding to a peak surface field of 265 MV/m; the two-port structure reached a mean accelerating gradient of 70 MV/m corresponding to a peak surface field of 266 MV/m. Both structures have the maximum surface field on the iris between the coupling cell and the first regular accelerating cell. Post-mortem inspection of both structures showed damaged surfaces only at this spot. The third structure tested, the planar one, reached an accelerating gradient of 50 MV/m. Its peak surface field remains to be calculated. Post- mortem inspection showed slight damage in the coupler region for this structure as well. All the field values quoted are measured for 15 ns pulse length, but higher values have been reached for shorter pulses.

Thanks to various refinements in the measurement apparatus and calibration techniques, it is now possible to achieve agreement to 1% between the measured probe beam acceleration and the acceleration predicted by the 30 GHz RF power measurement. A large quantity of data has been collected to characterize the RF breakdown process. One important observation is that these breakdowns give hardly any reflected power compared to more conventional RF cavities, but produce intense electron bursts. The intensity of these bursts is strongly correlated with a reduction of the RF power transmitted through the structure. Another particularly fascinating feature observed is that the light pulses emitted during RF breakdowns have a duration of hundreds of nanoseconds, which is much longer than the RF pulse itself.

Testing of a beam-powered single-cell cavity in the drive-beam line gave maximum surface fields without breakdown of 380 MV/m. Varying the temperature of this cavity in situ between –190°C and +200°C showed no significant variation of this maximum field.

The studies on coherent synchrotron radiation (CSR) effects in magnetic bunch compressors have continued with new experiments to measure the dependence of the emittance growth on the horizontal beam β-function. The design of a new CSR experiment to measure CSR shielding by the vacuum chamber has been completed, and the fabrication of the hardware components is under way; the four new dipole magnets needed will later be re-used in the injector of CTF3.

During the year 2000 no major modifications were made to the 3 GHz part of the CTF 2 beams. The modulators and klystrons, RF guns and 3 GHz travelling-wave structures worked very reliably, which allowed an operation that was more stable and efficient than in past years. A new, VME-based, DAQ system for the streak camera was successfully put into operation and replaced the obsolete PC-based system.

CTF3

The preliminary phase of the new CTF3 test facility was completely defined, so that work can start on modifying the LPI complex as soon as it becomes free in April 2001. The main goal of this preliminary phase is to demonstrate the technique of funnelling bunch trains of electrons to multiply the bunch repetition rate by up to a factor five at low bunch charge, compatible with the present LIL accelerating structures. This is in preparation for the RF frequency multiplication scheme using an electron beam, to be demonstrated in later phases.

208 Proton Synchrotron Division A new electron gun will be installed, which is presently being built by the LAL laboratory under a Collaboration agreement, closely following the design used for the CLIO machine (Collaboration pour un Laser d’électrons dans l’infrarouge à Orsay). Construction is on schedule, with installation at CERN foreseen for June 2001. The linac will be shortened to eight accelerating sections for which the design of the new optics and layout are complete. Modifications to the present EPA ring have been defined, in order to make the lattice isochronous with a dispersion-free injection region. A solution for the optics of the transfer lines has also been developed, and detailed drawings of the new layout have been prepared. Finally, an extensive machine development programme was pursued at LPI in preparation for the modifications foreseen, and for commissioning of the new machine. These included measuring LIL lattice parameters, beam emittances, bunch lengths and the EPA circumference, and testing the linac modelling and ring isochronicity.

For later phases of CTF3, a new front-end will be required, consisting of a high-current gun operating at a voltage of 140 kV, a pre-buncher, a sub-harmonic buncher, and a travelling wave buncher. For the hardware of the gun, an existing diode assembly is being modified by SLAC to fit the CTF3 requirements. LAL is starting studies concerning the gun electronics and the high voltage deck, as well as the design of the pre-buncher. SLAC has the responsibility for the optical layout of the injector and the work is well advanced. In parallel, the RF design of a 20-cell travelling wave buncher has started.

The existing LIL accelerating structures will need to be replaced by new structures, capable of accelerating the high bunch charge. A Tapered Damped Structure (TDS) has been developed, and a full-sized prototype was successfully tested with RF power up to 50 MW. An alternative design, a Slotted Iris Constant Aperture Structure, is also being developed. Computer simulations are very promising, and prototype work has started. A preliminary enquiry has been launched to produce these structures in industry, leaving open the choice between the two versions. The optics of the new linac will use triplet focusing, and the implementation details can now be finalized.

As RF power sources, the klystrons available from LIL will be used, together with a pulse compression system. This system has to produce longer RF pulses than the existing LIPS, with a flat-top in amplitude and phase. A scheme which uses a pre-programmed RF phase variation has been developed, and tests with RF power have started. Also, a very promising alternative to the twin-cavity system of LIPS has been developed, the Barrel Open Cavity, using only one cavity for storing the RF power; a model has been built and tested at low power.

For the later stages of CTF3 the INFN Laboratory, Frascati, will take responsibility for the delay loop, the combiner ring, the transfer lines, and the bunch compressors (both developing the layout and producing the hardware required). The optical layout of the combiner ring is well advanced, and the design of the delay loop has started. On the hardware side, a model of a strip-line kicker has been built, and studies concerning the RF deflectors and magnetic chicanes are progressing.

Proton Synchrotron Division 209 NUFACT (Neutrino Factory) Study

NUFACT Working Group

The Neutrino Factory Working Group (NFWG) created in May 1999 has been quite active in the year 2000. Contributions showing the latest ideas were made at various conferences and in particular at the NuFact00 meeting in Monterey. A CERN reference scenario has been worked out for a Neutrino Factory, and is shown in Fig. 7 in a schematic way. Collaborations have continued with many laboratories, in particular CEA, FZJ, GSI, IN2P3, INFN and RAL.

The first part of the reference scenario for a Neutrino Factory is the ‘proton driver’ which, in order to provide an intensity of 1021 neutrinos/year, should deliver a beam power of about 4 MW. In the CERN scheme, a linear accelerator delivering a beam of energy 2.2 GeV has been chosen. The reason for this choice is the SPL superconducting 2.2 GeV linac study that is based on the availability of LEP cavities, klystrons, etc. after the shutdown of that machine.

A possible H– linac 2.2 GeV, Accumulator4 MW ring + bunch

layout of a compressor p neutrino factory Magnetic horn capture Target Ionization cooling Drift

Phase rotation

Linac → 2 GeV µ Recirculating Linacs 2 → 50 GeV

Decay ring – 50 GeV ≈ 2000 m circumference

ν beam to near detector ν µ + ν π + µπ

ν beam to far detector

Fig. 7: The schematic NUFACT reference scenario.

This linac accelerates H– ions, operates at 75 Hz with a pulse duration of 2.2 ms, and has a beam current of 11 mA. The beam is injected into an accumulator (by charge exchange injection) and subsequently into a compressor ring to produce the necessary short bunch lengths of the order of nanoseconds. One hundred and forty bunches (at a frequency of 40 MHz) will be sent onto a target to produce short pion bunches. The pions will be collected and then subsequently decay into muons, which are captured. These muons must then have their energy spread and transverse emittance reduced, prior to their acceleration to 50 GeV. At CERN, there is

210 Proton Synchrotron Division considerable experience with magnetic horns for the collection of antiprotons, and in the conventional production of neutrino beams. It is therefore planned to investigate the possibility of using a magnetic horn for the pion collection in the Neutrino Factory.

Because of the high repetition rate and the large number of bunches, an RF system is proposed for the manipulation of the muons. The RF system will capture and phase-rotate the muon bunches, and will also be used in the process of ionization cooling of the muon beam. Further acceleration of the muons to 2 GeV is performed in a special linac with solenoid focusing up to around 1 GeV, followed by more conventional quadrupole focusing. Subsequent acceleration takes place in two Recirculating Linacs (RLAs) to an energy of 50 GeV. The muons are then injected into a storage ring (or, decay ring) where they are kept for the duration of their lifetime (1.2 ms at this energy). The muons decaying in the long straight sections of this ring produce the required neutrino beams. These straight sections point towards the neutrino detectors situated at suitably large distances.

The challenges on the accelerator side are enormous. The high intensities in the proton driver must be mastered with very low losses if hands-on maintenance is desired. The target problems (4 MW deposited) are more demanding than for a neutron spallation source, and the issues of ionization cooling must be addressed in order to increase the beam quality and intensity. The muon accelerators are also not easy, because acceleration must be rapid so as not to lose too many particles during their short lifetime (the muon lifetime is 2.2 µs at rest). Some of the technical problems are being addressed in experiments at CERN: for example, a modified 200 MHz cavity with locally-enhanced fields has been tested successfully in a high radiation area near the AD target zone; and a pion production experiment (HARP) made its first run, to obtain data that will allow an optimized target design. In outside collaborations, CERN has participated in a RAL experiment at TRIUMF (MUSCAT) to make measurements on muon scattering which will yield important data in the context of ionization cooling; and target experiments are in preparation at BNL (as well as at ISOLDE) to study the interaction with the high-intensity proton beam.

Superconducting H– Linac (SPL)

The suggestion was made some time ago to re-use the large amount of RF hardware from LEP, once it reached the end of its life, to build a new linear accelerator for H– ions. This machine could deliver 4 MW of beam power at 2.2 GeV, and could be the proton driver for a Neutrino Factory. If it were located at CERN it would dramatically improve the performance of the PS complex for all users of high beam intensity (i.e. LHC, CNGS, and AD) and also for the ISOLDE community whose medium-term plans for a second-generation Radioactive Beam Facility could then be realized on-site. The details of the SPL design have been refined during the year and a block diagram is shown in Fig. 8. The low-energy part using room-temperature structures has been optimized, and the debunching line at high energy has been properly designed. Superconducting multi-cell cavities for β = 0.8 and β = 0.7 have been built and have demonstrated useable gradients exceeding 9 MV/m and 5 MV/m respectively. The design of the chopper and its driving amplifier has progressed in close collaboration with other teams (Los Alamos and CEA, Saclay). The beam dynamics has been analysed for the whole accelerator and a satisfactory layout for the CERN site has been found which minimizes the cost of civil engineering work by re-using existing tunnels. A conceptual design report (CERN 2000–012) has been produced.

Proton Synchrotron Division 211 45 keV 7 MeV 120 MeV 1.08 GeV 2.2 GeV 13 m 78 m 334 m 345 m 3 MeV 18 MeV 237 MeV389 MeV

H– RFQ1 chop.RFQ2 DTL CCDTL β 0.52β 0.7 β 0.8 LEP-II dump

SourceLow energy section DTL Superconducting section

Stretching and collimation line

PS/Isolde

Accumulator ring

Fig. 8: The SPL block diagram.

Collaborations

Innovative ECRIS

The Innovative ECRIS Collaboration, with major funding from the Fifth Framework Programme of the European Commission and involving CERN, GSI (Darmstadt), INFN LNS (Catania), CEA (Grenoble) and UJF-ISN (Grenoble) made significant progress in 2000. Following the commissioning and testing of the 28 GHz gyrotron in Grenoble, the microwave power-pack was installed on SERSE, the superconducting ECRIS in Catania. In CW operation, the frequency scaling of the intensity (proportional to the square of the frequency) for a given magnetic field configuration (i.e. the confinement) was quickly confirmed. However, the resonant magnetic field at 28 GHz is about 1 T, and given the limitation on the maximum field available, it proved difficult to drive the source into saturation when trying to optimize the confinement. Additional tests also demonstrated the possibility to have an afterglow mode of operation, although the pulse was somewhat shorter than expected and somewhat less stable than the beam from the ECR4 Pb-ion source. The next stage of the project, installation of the 28 GHz microwave source on the normally-conducting ECRIS PHOENIX is now under way, with results expected in 2001. These results will form the basis for a design for a source giving 10 times the present intensity in linac 3 for the future CERN ion programme.

LIBO

The LIBO (LInac BOoster) project for cancer therapy aims to build a 3 GHz proton linac in order to boost the beam energy of a cyclotron from 50–70 MeV to 200 MeV. Such cyclotrons exist in many hospitals and small laboratories throughout the world, and the aim is to be able to treat deep-seated tumours with the higher energy beam. The project is a collaboration between the TERA Foundation, CERN, and the INFN (Milan and Naples). The PS Division has offered support in the RF design, low-level measurement and power testing at LIL of the prototype of the first LIBO module (62–74 MeV). This module is 1.2 m long and is composed of four tanks of ‘side-coupled’ cells. The tanks are connected by three off-axis bridge couplers that leave space

212 Proton Synchrotron Division for permanent quadrupoles on the beam axis, while constituting a single RF structure. During the year 2000, the 103 half-cell units that make up the module were brazed together, and a series of RF measurements and adjustments, before and after brazing, allowed an excellent field symmetry on axis of ±2.8% to be obtained. After the vacuum tests at the end of October, the module was installed in the LIL gallery and powered using a spare modulator-klystron (at 35 MW peak power).

The conditioning was rapid, and the module finally reached an accelerating gradient of 25 MV/m, which is well in excess of the design value of 15 MV/m. Indeed, the conditioning had to be stopped for lack of time, but there was clearly potential for increasing the gradient even further. These excellent results open the way to a re-design of LIBO for higher gradients, making the structure more compact and more suitable for hospitals. The next step for the LIBO module will be to move it to Catania, where it will be tested on a cyclotron beam, powered by a klystron provided by the medical accelerator firm Scanditronix, in the framework of a collaboration with TERA. In parallel, the technology will be refined and documented, in order to transfer it to industry.

Controls for IHEP Protvino

The controls collaboration is focused on the U-70 accelerator complex upgrade, to provide the IHEP institute with a simple, efficient control of their accelerator complex. The progress of the project is reviewed regularly by a common management meeting; the expected completion date has been confirmed for the year 2002, according to the updated planning of 1999. During the year, the activity concentrated on two major systems, the controls of the ejection and of the correction power supplies. These systems were provided with the full power of the tool-kit developed in previous years. A new timing system was included in this renewal. The autumn run was then used to validate the functionality and the reliability of the system. After that, the new facility was handed over to the operating team, and the U-70 physicists immediately benefited from the quality of their new control system.

On the hardware side, the mass production of the embedded micro-controllers was started, and will continue next year. Installation of the MIL1553 field bus, timing system and VME crates connected to the control system’s LAN was made as necessary. On the software side, the enrichment of generic control programs using the newly-available hardware facility continues. Populating the real time database, which is the kernel of the control software, shows the power and the flexibility of the ‘operation régime’ concept provided by this system.

Proton Synchrotron Division 213

SPS + LEP Division

Accelerator Physics

LHC Beam Optics, Beam Dynamics and Performance

Lattice Design, Correction Systems, and Collimation

The input files for optics calculations (MAD) can now be automatically generated from the LHC project databases. To ensure coherence between the optics model and the machine hardware, data from the Layout, Powering, Parameters, and Field Quality databases are all integrated. This is the result of collaboration between SL/AP and EST/ISS. MAD-generated files describing the 3D geometry of the LHC were delivered to EST/SU and the automatic consistency with the powering database information will facilitate the use of MAD sequence files for calculations and control during LHC operation.

The LHC lattice version 6.2 incorporates new solutions for IR2, IR3, IR4, IR6, IR7 and IR8. The optics in the experimental insertions IR2 and IR8 were modified to provide room for auxiliary collimators to protect the dispersion suppressor and arc magnets in case of injection failures. These collimators will be placed on the opposite side of the TDI absorber, in the warm region of the insertions, and have an approximate phase advance of 90° ± 20° with respect to the TDI. A study of particle losses in the case of mis-injected beams is under way to identify their location and to assess the collimation efficiency. Different beam loss mechanisms for equipment failure modes and the associated time constants were also investigated.

The optics of the collimation insertions IR3 and IR7 were adapted to the new layout and powering schemes, and constraints on the betatron phase advance in both rings were incorporated. The total tune of the machine was recovered by re-matching the insertions in IR4 and IR6.

The specification of the closed orbit correctors was revised and an analysis based on a local correction approach showed that special long correctors in the insertions can be avoided. Studies of orbit correction with two beams were also started.

At the end of the year 2000, a mini-workshop on the alignment of LHC magnets was organized to compare the tolerances obtained from beam physics considerations with realistic hardware and survey specifications. No significant discrepancy was identified. Simulation and Machine Development (MD) results on the measurement and correction of linear and non-linear optics were used to contribute to the specification for the BPM alignment, resolution, and linearity.

SPS + LEP Division 215 Dynamic Aperture

The requirements on the field quality of the lattice octupoles was specified. The effect of large multipolar errors from the warm quadrupoles MQW was also studied, and a reduction of these errors was suggested since they would otherwise dominate the LHC dynamic aperture. The results of a study for the ‘resonance-free lattice’ do not justify the introduction of additional chromaticity sextupoles at the ends of each arc to improve the robustness against b3 errors.

An extensive particle tracking campaign was performed to evaluate the long-term dynamic aperture of the LHC (version 6.1), with the aim of checking the reliability of the latest arc corrector schemes (mainly the new layout of the octupole/dacapole spool pieces) and of studying new options for the installation of the main magnets. The possibility of installing the dipoles in batches of 24 magnets coming from the same production line (‘mini-mixing’) was proposed and looks very promising. This installation strategy is much less constraining than the nominal one (where each of the 8 LHC arcs is assumed to be equipped with 154 dipoles coming from the same production line) without being detrimental to the dynamic aperture and to the possibility of correcting the multipolar field errors.

Beam–Beam Effects

Weak–strong simulations with the correct crossing schemes in all IPs, triplet errors from FNAL (USA) and KEK (Japan), and optimized corrector settings, confirm that the dynamic aperture during collision is significantly reduced by parasitic beam–beam encounters. A larger crossing angle is therefore suggested, which may possibly be the largest angle allowed by the hardware. Particle tracking over 105 turns indicates a loss of about 2σ for the dynamic aperture at injection, compared to the case without beam–beam interaction. Longer-term tracking studies are in progress. An analytical criterion based on resonance overlap was put forward to estimate the dynamic aperture due to long-range collisions. The effect of image charges on the long-range interactions was investigated and found to be negligible for the beam offsets currently considered. A more detailed study is currently under way.

The effects of ground motion on the beam stability and particle diffusion in the presence of head-on, beam–beam interaction were also studied. Diffusion coefficients are determined by particle tracking and analytical calculations, and are used in a numerical integration of the Fokker–Planck equation. The emittance growth over realistic time scales turns out to be negligible.

Coherent beam–beam effects in the strong–strong regime were further investigated during 2000. The proposed countermeasure, to split the tunes of the two beams, gives rise to coherent two-beam resonances resulting in emittance growth when Landau damping is active to damp the coherent modes. The studies were generalized to multiple IPs and the effects of symmetries and of phase advance adjustments between IPs were studied in detail. Long-range collisions were added into the model and have substantially changed the picture, both qualitatively and quantitatively. The appearance of two separate, uncoupled eigenmodes for the head-on and long-range interactions was explained and demonstrated by perturbation theory and multiparticle tracking. To study coherent beam–beam effects beyond the ‘soft-Gaussian’ approximation, a simulation code based on a Fast Multipole Method was developed in collaboration with TRIUMF (Canada).

216 SPS + LEP Division A new simulation program was also developed to study the coherent modes of some 3000 rigid bunches per beam, including the effect of head-on and long-range interactions. The oscillations of the bunches are followed around the self-consistent closed orbits, which are computed in advance. This will allow the investigation of the possible stabilizing effects of phase advance errors between the interaction points, bunch intensity variations, tune variations, etc.

The consequences of the finite-crossing angle on the coherent beam–beam modes were studied and evaluated for a realistic model. The excitation of synchrobetatron resonances was demonstrated and shown to have a stabilizing effect.

Impedance and Collective Effects

Several studies were performed during 2000 on impedance sources in the LHC. Given the number and variety of elements which have to be considered in collaboration with the different hardware groups, a list of general impedance rules for the design of the LHC beam pipes was established. In particular, the impedance of specific elements such as cold–warm transitions, microstations for ATLAS, and RF sliding contacts were evaluated. For the latter, recommendations and related specifications were presented at the LHC Beam Vacuum Interconnection Review. The possibility of using existing LEP vacuum valves in the LHC was considered and the resulting recommendations were forwarded to the LHC/VAC Group.

The original design of two LHC elements, namely the LHC septa and the TDI absorber, were found to be incompatible with the latest constraints imposed by the combination of vacuum, aperture, and impedance considerations. Fundamental modifications were proposed for both elements, and the corresponding solutions are currently under study.

Wakefields in the LHC recombination chambers were simulated in collaboration with INFN-Frascati and some potential difficulties associated with trapped modes were identified. The corresponding results were transmitted to the Berkeley Laboratory (USA), where these chambers will be built.

The need for a randomization of both the position and size of the pumping slots in the LHC beam screen, in order to avoid a coherent effect from trapped modes, was confirmed and discussed with the LHC/VAC Group. A Monte Carlo program simulating the synchrotron radiation flux around the entire LHC was developed, which includes realistic optics errors, closed orbit perturbations and allows for variations in the reflectivity of the chamber. Results from this program, combined with electron cloud simulations, were reported to the LHC Heat-Load Working Group.

The analytical models developed to compute the impedance of SPS and LHC kickers were completed, and reproduce fairly well the temperature rises observed in the SPS.

Based on the analysis of the experimental results obtained in EPA at the end of 1999, the study of the RF shielding properties of thin resistive layers continued. A computational procedure for layered vacuum chamber walls was developed during the year, and was validated by a second set of measurements performed in EPA at the end of 2000. The results obtained for some of the configurations tested will have a direct impact on LHC applications.

SPS + LEP Division 217 An updated review of the LHC programme with ions was completed and published. A new procedure was developed to compute Intra-Beam Scattering (IBS) using the Bjorken–Mtingwa model. This procedure is required to compute IBS growth times below transition energy, where the Piwinski formalism is known to be inappropriate.

Accelerator Physics Support and New Concepts in Beam Physics

The last contribution to the LEP optics consisted of re-matching the experimental insertions IR4 and IR8 to reduce the background level. This was successfully put into operation during the year 2000.

Electron Cloud Studies

A new series of electron cloud simulations were performed for the SPS, LHC, and the PS, following recommendations from the Chamonix X meeting and in response to new observations. In collaboration with the LHC/VAC Group, low-energy electrons elastically reflected at the beam pipe wall were modelled and shown to play a crucial role in the electron cloud build-up and for the corresponding heat-load on the LHC beam screen. Simulation results that include these reflected electrons seem to agree better with observations in the SPS using LHC-type beams, especially those with a gap of 12 missing bunches.

The possible degradation of LHC beam-position signals by the electron cloud was also examined and, in collaboration with the SL/BI Group, the angle and energy spectra of electrons hitting the vacuum chamber in the SPS and LHC were investigated. The energy spectrum strongly depends on the bunch length, and the magnetic field of the beam increases the angular spread of the electrons by about a factor of two. In addition, a high correlation between impact angle and energy is observed, which will need to be taken into account in the design of future diagnostics.

A novel multiparticle simulation code was developed to investigate the single-bunch instability driven by the electron cloud. First results are in agreement with analytic estimates, showing that the instability growth rate depends on the number of electron oscillations during the proton bunch passage, and saturates when this exceeds unity. There are also indications of a possible interplay between conventional and electron-cloud impedance.

Beam Optics Programs

The debugging phase of the accelerator design program MAD9 was found to be non-trivial, owing to its C++ class structure and to serious difficulties in modelling the common bending magnets in the two LHC rings. Optics studies for the LHC were consequently decoupled from MAD9 developments. A considerable effort went into upgrading MAD8 to include the following new features:

– The direction of the particle is now taken into account when going through a magnet.

– Two rings with common elements can now be matched simultaneously.

– Acceleration has been incorporated.

218 SPS + LEP Division A long-standing problem was also solved by modifying MAD8 so that it can compute the beta functions in the PS-to-SPS transfer line, which includes a 100% x-y emittance exchange. In addition, a new software project was launched, MAD-X, aimed at a modular and maintainable version of MAD that is based on MAD8 and is still compatible with the MAD9 syntax. The concept, layout, and main functionality of MAD-X, as well as the conversion procedure were defined, and a stripped-down, closed-orbit finding module without ZEBRA banks was produced and tested.

SixTrack90 is a new code that combines the map definitions of SixTrack with an existing overloaded Fortran90 Normal Form Analysis package. It can handle beam lines and includes some new features, such as hard-edge fringe fields, and is aimed at the parametric study of accelerator maps. Fast, symplectic map tracking was successfully applied to the LHC lattice version 6, with a simulation speed-up of a factor 10, however, multipolar field errors beyond order 7 can not be included in the map.

Machine Experiments

The efforts to reduce the SPS impedance in view of its future use as an LHC injector were followed by a series of detailed measurements. The reproducibility in the determination of the transverse impedance from the coherent tune shift is now better than 20%. There is a first indication of a small (about 10%) decrease in impedance from the measurements performed in 1999 and 2000. In addition to the measurements at 26 GeV, a dedicated MD session allowed the verification of the proportionally smaller effects at 120 GeV with unprecedented precision. These baseline measurements were complemented by growth/decay rate measurements as a function of chromaticity, and multiturn beam-position recordings as function of intensity. A broadband impedance is found to be inadequate to model the observations in the horizontal plane.

Several experiments were performed to measure resonance driving terms and to localize sources of non- linearity at 26 GeV and 120 GeV in the SPS. The results are encouraging and are being used to validate the SPS lattice model and the analysis of multiturn beam-position data with kick strength for future application in the commissioning of the LHC. Dynamic aperture and driving-term experiments were also performed at HERA-p (Germany) and at RHIC (USA), but with limited success because of the insufficient quality of available beam instrumentation and/or hardware failures.

Besides contributing to SPS experiments on electron-cloud effects, a transverse beam echo following two dipole kicks was measured in the SPS for the first time. One long SPS MD session in 2000 was dedicated to measurements of the energy loss of coasting proton beams at 120, 170 and 220 GeV, in an energy region where synchrotron radiation is expected to be partially suppressed by the presence of the conducting beam pipe. A similar experiment was also proposed and participated in at HERA. A combined analysis is in progress to search for the first experimental evidence for synchrotron radiation with screening from protons.

SPS + LEP Division 219 Studies on Future Accelerators

CLIC Studies: Beam Delivery System and Damping Rings

At the interaction point, the vertical spot-size increase due to synchrotron radiation in the detector solenoid field and its fringe was shown to be significant. This sets a tight upper bound on the maximum possible total crossing angle. For a 4 T solenoid field this limit is about 20 mrad, i.e. equal to the minimum angle required.

A number of short final-focus systems with non-zero dispersion across the final doublet were studied for CLIC at 3 TeV. Unfortunately, all draft optics created so far fall well short of the desired luminosity. A collaboration set up with the University of Valencia aims at improving the performance. Analytical approaches for even shorter final focus systems were explored, and specifications were completed for a system based on RF quadrupoles.

By evaluating the combined effect of ionization heating and image currents, it was shown that, at several locations in the final focus, the spoilers can survive the full impact of an undiluted beam, provided they are made from the proper material (carbon or beryllium). Simulations launched for studying failure modes in the linac and quantifying the implied emittance growth, showed that in some cases there is a blow-up by several orders of magnitude. Ultimately this will determine the minimum beta functions required at the collimators.

Expressions for collimator wakefields were compiled and programs for studying scattering from residual gas or thermal photons installed. A collaboration set up with DESY-Zeuthen aims at evaluating muon generation and propagation in the CLIC beam delivery system, using software tools developed for TESLA. Layouts with an overall crossing angle and example parameters were explored for photon–photon collisions at CLIC, and potential problems were identified.

A conventional optics was designed for the damping ring using 3 TeV parameters and based on a TME arc lattice using established optimization algorithms. It was shown that IBS growth rates in such a design are orders of magnitude higher than the synchrotron radiation damping. The same conclusion will hold for the 1 TeV damping rings. In addition to IBS, some novel instabilities may have severe growth rates. Estimated growth times for the fast beam-ion instability are about 0.6 turns at 1 ntorr, and 14 turns for the electron-cloud instability. In response to the above findings, the design strategy was recently changed in order to explore the option of a ring with a much larger circumference, such as that of LEP. In such a ring, radiation damping, IBS and quantum excitation would occur almost exclusively in the long wiggler sections.

Final-focus stabilization problems were vigorously addressed in collaboration with other laboratories, and a comprehensive R&D programme has now been launched at CERN.

Neutrino Factory and Muon Collider Studies

Neutrino factory modules were developed to the requirements established by the Neutrino Oscillation Working Group at CERN; in particular the proton driver, the recirculating muon linear accelerators and the muon storage ring. Instabilities, space charge and electron-cloud effects were also investigated in the proton driver. The design of the re-circulators has now been automated.

220 SPS + LEP Division Optics studies for triangular and bow-tie geometries were performed with a view to the design of a muon storage ring. The effect of fringe fields was also investigated, and led to the recommendation to lengthen some quadrupoles in order to lower their gradient and to reduce the loss of dynamic aperture. Other studies concerned the identification of additional electron losses in the dispersion suppressors due to muon decay in the straight sections. A logical R&D programme for muon acceleration was proposed, including engineering and simulation milestones.

Beam Instrumentation

During 2000, the Beam Instrumentation Group concentrated mainly on its future tasks of providing instrumentation for the LHC project, for the upgrade of the SPS as LHC injector, and for the CNGS project. The other task of note concerning the SPS was the continued renovation of the instrumentation in the experimental areas. Apart from the spectrometer project, some other smaller performance improvements and protection against increased radiation levels, the LEP instrumentation was maintained at the performance level of 1999.

LEP

A total of nearly 200 collimator blocks and the four synchrotron light monitors were prepared and kept available during the whole run despite the high radiation doses experienced. The Beam Orbit Measurement (BOM) system also performed well throughout its final year of operation.

A high-precision measurement of the modulation in tune resulting from the modulation of the field gradient in a quadrupole (‘K-modulation’) was tested on LEP for possible use in the LHC. This enabled the average β-function at the modulated quadrupole to be measured with a precision better than 1%. The results are consistent to within 4% with the method of β-function determination using the analysis of multiturn position measurements of excited betatron oscillations. In addition, the new method requires less excitation of the beam and can therefore also be carried out during collision.

After being commissioned in 1999, the LEP spectrometer project continued in 2000, with the help of the SL/MS Group. The aim of this project was to measure the LEP beam energy to an accuracy of 10–4, i.e. to within 10 MeV at 100 GeV. This requires an accuracy of few parts in 10–5 both on the Spectrometer Magnet Bending Injection (MBI) dipole integral field and on the six associated Beam Position Monitors (BPMs). With the aim of improving the accuracy and in collaboration with SL/MS, all the six BPMs were motorized using stepping motors for the LEP run in 2000. This allowed the displacement and remote control of the transverse position with a resolution of a few micrometres. The BPM electronics was tested in the laboratory to determine and verify the available operating range for various parameters. The spectrometer was also used under different beam conditions to try to observe systematic variations. In order to correct the position measurements, the information of the BPM monitor movements was used. Two new 3-axis fluxgates were installed to improve the monitoring of magnetic fields due to the Earth’s magnetic field and any stray fields. This allowed a correction for the bending of the beam in the drift regions due to the environmental magnetic field to be applied for the first time. All the Wire Position Sensor (WPS) cables, which were heavily damaged during the LEP run in 1999, were replaced. Additional lead shielding was added to the WPS sensors on both

SPS + LEP Division 221 ends of the spectrometer in an attempt to reduce the effect of synchrotron radiation on the outermost BPMs. At the end of the LEP run, the MBI dipole was removed, and it was decided to re-measure its integral magnetic field in order to finalize the spectrometer’s overall performance.

Experimental areas

Instrumentation continued to be maintained in the SPS Experimental Areas, and new instruments were installed at the EA physicists’ request. However, the main activity in these zones concerned the EA Renovation Programme, which is now well under way. This aims to replace all the old instrumentation and associated electronics, upgrade the EA power supplies and to install a new controls structure linked to the PCR. Regular meetings ensure a close collaboration with the SL/EA, the SL/CO and the SL/PO Groups. Collection and analysis of user requirements is progressing, with a naming convention having been developed and glossary of terms written. A new Ethernet network, the SL/CO supported timing system, and VME-based experimental scalers have already been installed. Tests are currently being carried out on a new scripting language to replace the old NODAL software, and the development of a new trigger following an equipment- oriented approach is nearing completion. The renewal of the vertical slice spectrometer will allow the performances of these new systems to be ascertained in 2001. The monitoring of the barracks in the West Area will in future be done in collaboration with the ST Division.

SPS

The SPS beam-position measurement system, MOPOS, performed well during the whole of the year. A new method of online calibration was implemented early on, which significantly reduced the time required to perform a calibration of the whole system. New functionalities continued to be added to the multiturn analysis program, which has become an important tool during machine development studies.

The Optical Transmission Radiation (OTR) monitors were extensively used in the TT10 transfer line for the investigation of injection matching and in the hunt for coupling sources in the PS-to-SPS transfer. Four monitors are now installed in TT10 with an additional monitor available in the SPS ring. The acquisition system now allows the capture of a 2D beam profile every eight SPS turns, with up to four of these profiles captured per acquisition.

SPS as LHC Injector

Progress continued to be made with the LHC prototype emittance monitors in the SPS. Turn-by-turn measurements using electrons focused by a magnetic field were performed for the first time with the Ionization Profile Monitor (IPM) using a multi-anode photomultiplier. The problem of the signal tails observed during 1999, with the IPM in CCD mode, was solved by reducing the aperture of the objective lens so reducing the non-linear effects. Both horizontal and vertical profiles over a full SPS cycle were available in 2000 using the nitrogen luminescence monitor. The precision of the results of both of these instruments was validated with wire scanner measurements.

222 SPS + LEP Division During the SPS ‘25 ns run’ in May, when 84 bunches separated by 25 ns were accelerated to 450 GeV, many parasitic measurements were performed using the Head–Tail monitor. This instrument is capable of distinguishing transverse motion within a single bunch, and is envisaged as an alternative means of measuring chromaticity. The results obtained showed a surprisingly good linearity when compared to the radial steering technique normally used for such chromaticity measurements. However, a correction factor, which varied with energy, of between 0.4 and 0.6, was found to be necessary for absolute measurements. More studies are planned for 2001 to try to determine the origin of this factor. As a by-product of these measurements, this technique was found to be a good way of measuring the variation of chromaticity with transverse position. For most of the year this was also the only monitor capable of distinguishing the transverse movements of all the bunches in an LHC batch. Hence, it was also extensively used during machine studies to try to understand the problems of electron cloud build-up along the batch.

The Individual Bunch Measurement System (IBMS) was commissioned in 2000 and was able to measure the intensity of each individual bunch in an LHC batch. Three systems are currently installed, one in TT2, one in TT10 and the other in BA1 of the SPS ring. Several problems were encountered, mainly with the hardware. The fast current transformers on which the system is based were found to have a non-negligible droop, a problem that was compounded by resonances caused by the old housings in which they were mounted. This meant that it was not possible to cross-calibrate all three systems. During the year an alternative housing was therefore designed, which is now being built by industry. This will be installed during the 2000/2001 shutdown along with a new, low-droop beam current transformer. Another problem arose from the fact that the timing signals were generated by the RF system in BA3 but used by the IBMS system in BA1. Since the beam transit time between BA3 and BA1 varied during acceleration, while the timing transmission remained constant, a de-phasing was seen between the acquisition and the beam, which meant that data was only valid over small energy ranges. A means of rephasing the system using software was developed during the year and will be operational in 2001.

A first complete prototype of the LHC orbit acquisition system was tested in 2000, using a special BPM with LEP buttons, which was installed in LSS4 during the 1999/2000 shutdown. For the last month of the SPS run this was made available to the SPS operators, and replaced the Head–Tail monitor as the instrument to study bunch-to-bunch transverse instabilities.

LHC

In order to have a systematic approach to the design of instruments for the LHC, a BI Specification Board and a BI Technical Board were set up in 2000. The Specification Board will be responsible for defining the functional specifications for each of the LHC instruments. It has already collected the requirements arising from linear and non-linear beam measurements to finalize the specifications of the beam-position measurement system for the LHC. It has also produced the functional specifications for a high-sensitivity longitudinal profile monitor with the aim of measuring the distribution tails, ghost bunches, and the un- bunched fraction of the beam. The Technical Board will be responsible for ensuring that the technical choices for each instrument meet the functional specifications, and will provide a common interface between BI and its representatives from the various LHC working groups.

The calls for tender for both the LHC button monitors and the associated cryogenic cables were launched in the early part of 2000, with the successful companies selected in the July and December Finance

SPS + LEP Division 223 Committees, respectively. The first pre-series units are expected to arrive in the first half of 2001. A prototype coupler pick-up has also been built and tested, and the market survey for the supply of its feedthroughs is currently being prepared.

The first and second prototypes of the Wide Band Time Normalizer (WBTN) acquisition card were successfully built and tested. The performance was found to be even better than expected, and satisfies most of the functional specifications of the beam-position measurement system for the LHC. The recent lowering of the nominal lead-ion intensity does, however, mean that some modifications will still be required.

The first prototype Digital Acquisition Board (DAB) was built in TRIUMF (Canada) and tested at CERN. This card will process all the data received from the WBTN, to provide the orbit and trajectory measurements for a given pick-up. The first tests of the complete system were a great success, allowing one system to be used in a semi-operational way in the SPS by the end of the year. One of these DAB cards was also placed in the TCC2 radiation test zone, and its functioning remotely checked during irradiation. Severe problems with single event upsets of the SRAM memory were found, as was expected. These results and the official green light for placing fibre optic cables in the LHC tunnel have led to a rethink of the orbit system topology, which will now use fibre optic links to allow all vulnerable components to be placed in areas protected from radiation. Such a system will be built and tested in 2001.

Two candidates for a future luminosity monitor in the LHC were tested with beam in the SPS experimental areas. A monitor based on an ionization chamber was built and tested by LBNL (USA), and the current design was seen to be incapable of operating at the required 40 MHz. The other monitor to be tested used a CdTe detector and gave good results, but will have to undergo further radiation testing to confirm that it can withstand the high doses that it will encounter in the interaction regions of the LHC.

A beam-based method was developed to measure the multipolar field components of the low-beta quadrupoles using the BPM system and the tune-meter. First tests performed at RHIC in collaboration with BNL (USA) gave promising results.

Beam Transfer

SPS and LEP Operation

The fast pulsed magnet systems in both the SPS and LEP operated very reliably. The only mishap of note concerned the LEP injection kickers where two fans in the pulse generators failed consecutively. Short access periods were then used to systematically replace all fans.

The horizontal deflecting kickers (MKDH) of the SPS beam dump system operated with two new, solid- state switches instead of the original ignitron switches, which contained mercury. After their successful operation in 2000, the remaining ignitrons will be replaced during the 2000/2001 shutdown.

New vacuum pumping modules were installed during the 1999/2000 shutdown on the girder of the electrostatic septa (ZS) in LSS6. This is the first part of a general upgrade of the extraction channel vacuum

224 SPS + LEP Division equipment. Following problems with the production of new units, pendulum shutters were installed in positions 1 and 2 in both extraction channels, with linear shutters installed in positions 3 and 4. During the 1999/2000 shutdown several problems occurred in the extraction channels that resulted in the accidental venting to atmosphere of the ZS. Both ZS systems therefore had to be baked and re-conditioned. This work was completed in time for the cold check-out. A serious vacuum leak then occurred on one of the ZS tanks, which was found to be the result of prolonged corrosion near the vacuum weld. The tank was changed and the extraction re-conditioned in time for the start of setting-up with beam. However, an inspection of all other installed and reserve ZS units showed that a further nine tanks had signs of corrosion in similar locations. As this type of corrosive attack cannot be stopped, an urgent campaign to construct 10 replacement ZS vacuum tanks was launched, and the fabrication of new spare ZS units will become a high priority over the coming years.

For the magnetic septa, the RF shielding programme was completed with the planned exchange of three units in LSS6 and the addition of shields for the remaining septa.

During operation in 2000, there was a total of 51.9 hours SPS down-time due to the extraction channels, some 11.7% of the total for the SPS over the year. Most of this was due to the exchange of the electrostatic septum ZS1 in LSS2, which failed with a suspected broken anode wire causing a short-circuit to earth. The analysis of the situation and preparation for the intervention were complicated by confusion over the induced radioactivity measurements in the area. As a result, new procedures for this type of measurement are now in place and the relevant equipment has been upgraded. When the new ZS was installed, the conditioning went very well with less than 24 hours lost for leptons.

Another major incident concerned the magnetic septum MSE3 in LSS6, which, during the Pb run, produced a leak of the high-pressure cooling water from the septum coil into the machine vacuum. Since the MSE were, at this time, only being used at low current for lepton injection, the leaking tank was disconnected and the coil evacuated with a roughing pump. The strength of the four remaining MSEs was then increased to compensate for the loss of one unit. Other minor problems included two broken flow-meters, which has prompted a re-evaluation of the design, and the replacement of several permanent magnets on the pendulum shutters.

For the LEP separators, a programme of preventative maintenance was carried out during the 1999/2000 shutdown, with a renovation of the 20 dielectric liquid cooling stations and the renewal of eight high-voltage cables in IP7. Shortly after the start-up, it was discovered that a change in the LEP optics required the separators in IP4 to operate at fields some 20% above nominal, in order to give sufficient separation at the experimental points for injection energy. This was achieved by increasing the operating voltage to close to its maximum level, which involving replacing the eight 160 kV high-voltage generators by new 200 kV units, followed by a careful reconditioning process. Despite their operation at higher field levels, the performance of the separator system continued to be good, with only a few sparks occurring and no associated beam loss.

The down-time of LEP due to the separator system was very low at only 11 hours, representing 2.9% of the total down-time for 2000. The total down-time of the separator system over the four years of LEP2 operation, covering the entire high-energy run (> 90 GeV), was a remarkable 42.5 hours, less than 0.25% of the total of 17 500 hours scheduled for operation.

SPS + LEP Division 225 The performance of the electronics and controls for the SPS and LEP kicker magnets, the SPS extraction channels, the LEP separators and the SPS target sector equipment was once again very good. No major problems were encountered despite the large amount of upgrade and maintenance work carried out during the previous shutdown. The year 2000 was also the first year of continuous operation for the new electronics of the SPS target sector. Based totally on industrial components, this system has proven its robustness, working without any problems for the entire operational period.

The development of a highly stable and precise AC/AC power supply continued in collaboration with industry. Using fast switching techniques, these are aimed for the thyratron heater system used in various kicker units. Further effort also went into high-precision magnetic measurements of the SPS injection kickers, with several different measurement techniques and probes being designed and evaluated. Inductive and capacitative probes developed in 2000 will be re-used over the coming years for the magnetic measurements of the SPS extraction and LHC injection kicker systems.

The modernization of the control system for the SPS extraction channels was started with the replacement of the electronics for the magnetic septa in the North extraction. This now employs the same architecture as used for the control of the SPS target sector equipment and the SPS injection kickers. This work will profit from the experience gained with these earlier projects, with the reproduction of controls such as the high- precision positioning system developed for the SPS targets. Much work was also put into the simplification and optimization of the cabling between the septa (typically located in highly radioactive areas) and their control electronics in order to reduce the intervention time required and to improve the reliability of the overall system.

SPS as LHC Injector (SLI Project)

During the 2000/2001 shutdown the majority of the SPS injection kickers (MKP) will be replaced with new kickers fulfilling the requirements for the injection of the LHC beam. To prepare for this installation, 12 new kicker magnets were assembled during 2000, with some of them being successfully tested under high voltage. The new kicker magnets have a shorter rise time than the old system and a flat top ripple of less than ± 0.5%. To shorten the rise time, the characteristic impedance of the magnets and pulse forming networks (PFNs) was increased to 16.6 Ω and 8.3 Ω, respectively, with the PFNs also equipped with special ‘speed-up’ cells. Six operational PFNs are presently being equipped with the new coils and front cells that were produced during the year. A prototype PFN has been working successfully at 60 kV, delivering the required pulse to a new magnet.

New SPS extraction kickers (MKE) will be installed in LSS4 during the 2002/2003 shutdown, to send beam to the LHC and the CNGS facility. The layout of the MKE system in LSS4 and LSS6 was defined, taking into account the required kick strength and the physical aperture of the system. Five new MKE magnets will be required, with a larger physical aperture than the current models, while four of the older MKE magnets will also be re-used. Measurements of the rise time on the present MKE system indicate that the magnet length can be maintained. The possible use of a diode instead of a classical thyratron dump switch was tested experimentally. For both the MKE and MKP system, measurements on the heating of the ferrites by the beam were carried out. As a result it was decided to water-cool the MKE magnets.

226 SPS + LEP Division The design of the magnetic septa for the new LSS4 extraction was also finalized, with a conventional septum (MSE) being preferred to the new pulsed septum (MSP). The construction of the components for the extraction channel has started, with the launch of the calls for tender and the first deliveries foreseen to take place in 2001. The production of the six septa needed for the extraction is already well under way, to be ready for installation in the 2002/2003 shutdown. The modifications to the LSS4 infrastructure, concerning platform extension and reinforcement, are approved and will begin during the 2000/2001 shutdown.

Modifications to the extraction channel in LSS6 to accommodate a diluter element to protect the ZS septum were defined and the implications for the SPS were investigated. The ZS girder will be lengthened to accommodate six units, one of which will be the mobile diluter. Work on the transformation has already started.

Concerning the pumping port shielding, the installation of the ‘third dipole’ shield went as planned during the 1999/2000 shutdown. As a result, the series production of the remainder of the shields was launched in 2000, with the emphasis put on design and prototyping in order to be ready for the installation programme foreseen for the 2000/2001 shutdown. The production is going as planned, with several batches already delivered to CERN and with installation in the SPS having starting on schedule.

The new SPS internal beam dump (TIDV) using a graphite core was installed at the beginning of the year and performed as required. Two spare graphite cores were completed and tested during the year with one of these being mounted in its iron shielding, to serve as a ‘ready-to-use’ TIDV spare.

Significant effort also went into preparing for the upgrade of the MKP control system. Good progress was made with the definition of the hardware and software architecture and with the production of all hardware to be installed during the 2000/2001 shutdown. The slow controls part of the system will be completely rebuilt using industrial components. SIEMENS S7-300 programmable logic controllers (PLCs) and remote I/O will be connected via PROFIBUS-DP field-bus segments to a SIEMENS S7-400 master PLC controller. A SCADA system (WINcc) will be used for local control facilities and supervision. The fast timing will be reorganized on the basis of the actual hardware in order to fulfil the requirements of the SPS during multicycling operation and to obtain the requested 5 ns synchronization pulse between the different magnet signals. Work also started on the integration of the new MKP control system into the SPS2001 software project. In order to retain the possibility of integrating the existing G-64 hardware into the new environment, an interface between G-64 and PROFIBUS-DP was developed.

CERN Neutrinos to Gran Sasso (CNGS Project)

Much effort went into the technical co-ordination of the primary proton beam line. The civil engineering around the proton beam line was carefully checked, and the transport of equipment through the access gallery and the primary beam tunnel is being studied. All parameters for the new main dipoles and quadrupoles were defined. The requirements for the power converters were also defined, and a preliminary trajectory correction scheme was studied. Definition of the beam instrumentation and vacuum component requirements is under way.

SPS + LEP Division 227 Studies are currently being undertaken to optimize the design of the CNGS target. The energy deposition was evaluated for different beam parameters and target geometries, along with the influence on the neutrino yield. A detailed study of the origin and distribution of all neutrino species was also performed.

LHC Transfer Lines and Injection (LTI Project)

The intensive follow-up and co-ordination work continued for the LHC injection transfer lines, TI2 and TI8. Many groups both inside and outside the SL Division are involved in this project. For further details, see their respective annual report contributions.

The design study of the vacuum system for the injection septum magnets (MSI) is in progress, but advancing less rapidly than expected. The production of the bulk of the vacuum chambers at BINP (Novosibirsk) is ongoing. The design study for a new transport and installation vehicle is completed, with the market survey under way. Work on the layout and required performance of beam instrumentation other than position monitors, such as profile monitors, beam current transformers and beam loss monitors, is nearing completion. The construction of beam dumps (TED) and safety stoppers (TBSE) for the beam transfer lines TI2, TI8 and TT40 has started, with one TED core already completed.

Within the framework of the LHC Injection Working Group the injection beam stopper (TDI) was remodelled with its final design. Design work on the TDI assembly is now under way. Impedance studies revealed that it is necessary to introduce a beam shield in the TDI tank in order to avoid excessive heating of the device and the possible deterioration of the beam. Tracking studies of swept bunches confirmed the usefulness of additional injection collimators in the LHC and of shielding for the D1 magnets (TCDD).

Concerning the LHC injection kickers (MKI), the series production of the resonant charging power supplies and the PFNs was launched at TRIUMF (Canada), following the successful tests of the prototypes at CERN. The PFNs will be able to produce pulses with an adjustable flat-top duration of up to 7.8 µs, to be able to accommodate alternative injection schemes. New compact switches based on thyratrons have been designed, which should improve the reliability and considerably ease maintenance compared to existing equipment. The development is well advanced and prototypes are under tests. The construction of the prototype magnet is somewhat late owing to difficulties in the manufacture of the mechanical components by industry.

Other LHC Activities

Two pre-series pulse generators for the extraction kickers (MKD) are under construction containing the modifications that were derived from the prototype, and will be used to validate the assembly procedure for the series production. Market surveys for the magnet coils and cores gave positive results after efforts in promoting the project and visiting potential manufacturers. The competitive tenders will now be launched in 2001. The market survey for the ceramic vacuum chamber is also nearing completion.

The dilution path on the absorber block has been re-optimized, which has allowed the apertures of the horizontal and vertical diluter kicker magnets (MKB) to be defined. This means that the design of the magnets and generators can now be finalized. The construction of a prototype vertical diluter generator is already under way.

228 SPS + LEP Division The impact of swept bunches on the various components of the extraction channels was studied and simulated in detail. This has led to proposals for protection devices upstream of the extraction septa and at other locations in the LHC. The energy deposition simulations of the beam dump absorbers (TDE) were updated to reflect the latest changes in the LHC beam parameters. Studies on the structural effects of a total beam dilution failure have continued through an external collaboration.

Work was also started in 2000 on the rapid acquisition system of the HV generator and magnet waveforms to be used for the post-mortem analysis of the LHC extraction kickers. Two studies were undertaken in parallel, one to determine the minimum acquisition requirements for a reliable and complete post-mortem analysis, the other to explore industrial data acquisition products.

Controls

The mandate of the SPS/LEP Controls Group is to define, deploy and maintain the controls infrastructure used to control remote equipment located around the machines to diagnose, drive and control the particles contained in the accelerators. The main activities in 2000 can be categorized into four different areas:

– The passive and corrective maintenance of the complete controls infrastructure.

– The developments undertaken for the current infrastructure.

– The definition and development of the future infrastructure.

– Major contribution to several LHC working groups.

Maintenance of the Current Controls Infrastructure

Day-to-day surveillance and maintenance of the SPS, LEP, and ST controls infrastructure was carried out using management tools (Xcluc for the front-ends, NNM for the network, etc.), which allowed most problems to be solved before they actually affected machine operation.

Developments for the Current Infrastructure

The current SPS/LEP controls infrastructure is still evolving and several enhancements, developments, and new installations took place during the year 2000.

The CERN alarm package was upgraded, and now implements a new fault state reduction algorithm, together with Oracle forms and new console features.

A Web working group was set up to study the utilization of the Web inside the controls infrastructure, in order to reduce our involvement in that domain as much as possible by making use of the centralized CERN Web Services. This working group concluded its work by installing a local Web service for Web pages needing local data access and by exporting all the other Web pages to www.cern.ch.

SPS + LEP Division 229 Support was given to the LHC String2 project in terms of network and front-end infrastructure and with software development for the integration of the magnet protection diagnostic system.

The current LEP communications network had to be re-routed via the surface in view of the LEP dismantling. This was done by pulling long lengths of optical fibres inside the LEP perimeter and by using the SDH protocol to gradually replace the TDM. In addition, the LHC-TTC timing system was installed in the PCR and tested with beam in SPS North and West areas. The status of the GPS systems was constantly monitored, with any malfunction resulting in the appropriate expert being informed via the GSM telephone system.

Several new Linux platforms were installed inside the controls infrastructure, mainly to support our local services such as Web servers, printer servers and Java platforms. Another breakthrough was the outsourcing of the monthly alarm database update to an external firm (GTD) in the framework of a software maintenance and development contract elaborated by ST/MO. This outsourcing started in November 2000 with a knowledge transfer phase, and was followed in January 2001 by GTD performing the work under SL/CO supervision.

Future Controls Infrastructure

The use of Oracle8 for the CERN alarm package was explored during 2000 and a prototype of the future alarm system using the PVSS SCADA tool is now being studied. On the application software side, several developments are under way. Two major software projects, one to review the operational software of the SPS ring (SPS-2001) and the other for the SPS Experimental zones (CESAR) made significant steps forward in 2000. These propose to make intense use of new and modern software techniques, such as object-oriented analysis and the Java language. During 2001, SPS-2001 and CESAR will deliver their first pieces of software for operation. All the new software will make use of the results of the middleware project whose mandate is to provide the modern software communication architecture and services required to operate both the PS and SL accelerator complexes. Here again, a first working version will be delivered in 2001. Finally, the future controls infrastructure for the LHC will demand specific requirements such as real time networking, new fileserver and application support, OO language support, etc. For this reason, a special LHC Controls Project has been set up, whose progress can be found as a separate entry in this SL annual report.

LHC Working Groups

Members of the SL/CO Group are presiding over several LHC working groups. The LHC Timing Working Group (TIMWG) continued its investigations into global timing distribution for the LHC. A GPS-based system with IRIG-B transmission was successfully tested during the year to provide low-jitter timing information. This working group also approved the adoption of the TTC system to transmit fast timing signals for the LHC. The Radiation Working Group (RADWG) maintained an online radiation test facility in the TCC2 target zone of the SPS North extraction region for the testing of electronics destined for the LHC tunnel. Measurements and simulations performed in 2000 found that this area is subjected to radiation with similar characteristics to that which is expected in the regular arcs of the LHC tunnel. Electronics qualified in this zone can therefore be said to be qualified for installation in the LHC arcs. It is a permanent, operational installation and more than 20 experiments, involving a wide range of electronic components, were carried out in 2000. The Tunnel Electronics Working Group (TEWG) has a mandate to rationalize the amount and the

230 SPS + LEP Division type of electronic equipment that will be installed in the LHC tunnel and alcoves. As a result of the 2000 radiation test campaign in TCC2, several pieces of equipment that were foreseen to be installed in the LHC tunnel will instead have to be installed in other locations. This has meant that space management in the LHC alcoves has become very difficult. A proposal was therefore made to install double-capacity equipment racks to try to alleviate this problem.

LHC Controls Project

The Controls and Operations Forum (http://lhcp.web.cern.ch/lhcp/TCC/PLANNING/TCC/Forum99/ Forum.htm), held in December 1999, recommended that an interdivisional project should be set up for the control of the LHC. In January 2000, a Core Team was created to start up the project. This core team included members from the SL/OP and SL/CO Groups as well as from the LHC Industrial Automation Group.

A Workshop (http://cern.ch/lhc-cp/Workshop/2000-04/Slides.html) was held in April 2000 with the aims of confirming the project mandate and fixing the project goals, with particular emphasis on the first year of the work. The major goals of the project are to make efficient use of the available resources, to ensure consistent technical choices, and to make certain that the final product meets the requirements for accelerator operation and development. Activities will include monitoring the technical work within the participating groups, minimizing the diversity of the technical solutions applied in the control system, and initiating the creation of generic services. Nineteen groups in five divisions joined the project and an essential activity will be the establishment of an integrated planning for controls activities for the LHC machine and for technical services. The project team is also responsible for the specification and production of the application software for the LHC control room. The workshop identified the following priority topics for the first year:

– Middleware.

– Real time control.

– Systems built from industrial controls components.

Middleware

In this context, ‘middleware’ is defined as the software providing the means of exchanging data and commands between different parts of a distributed control system. In the LEP era this functionality was provided by an in-house RPC package, which does not have the features necessary to support modern software languages or the possibility of integrating industrial systems. Different middleware approaches were identified at the workshop covering the experiments, technical services, and the accelerators. A project to provide replacement middleware for the accelerators was extended to include representatives from the technical services team. At the end of the year, this effort resulted in working prototypes based upon CORBA, a vendor- neutral product and a commercial ‘MOM’ or message oriented middleware. Work to develop a CERN-wide middleware is scheduled for the second phase.

SPS + LEP Division 231 Real Time Control

The requirement identified at the workshop was for control loops with bounded, slow (1–10 Hz) repetition rates. The motivation comes from the need to tightly control the beam parameters in the presence of non- reproducible magnetic field errors. Commercial communication and computing systems exist which satisfy these requirements, but they do not currently occupy leading roles in the personal computing market. The recommendation to dedicate resources for a working group to study the control issues was delayed pending the clarification of the operational and physics requirements to be met by this system.

Industrial Controls Components

The workshop also brought together specialists working with industrial fieldbuses, PLCs and SCADA systems. For the LHC the slow controls applications will replace laboratory type systems, such as real-time VME, with these rapidly evolving industrial components. Issues raised at the workshop included the need for central support for groups using these systems. The CERN Controls Board has recommendations for PLCs and fieldbuses, but guidelines for SCADA are now also required. Additionally, the integration issues involved with these systems need to be tackled. During the year the Controls Board therefore focused on the need for a SCADA recommendation and the integration of these systems through middleware. A sub-project was recently established to further address these and other issues.

Other Activities

Initiatives were also launched in other areas. The LHC Analysis Working Group was set up with the principal aim of understanding the operational needs of the LHC control system. These will be fed into the strategic decisions on control system architecture, in particular concerning the domains of real-time, timing, middleware, and the so-called ‘multipole factory’. It is also important to anticipate the necessary low-level equipment functionality and to ensure that this will meet high-level requirements. A core team representing the SL/AP, SL/OP and SL/CO Groups is now in place to tackle these issues. It has already begun to determine the requirements and to build operational models for general LHC operation, such as injection, collimation, accelerator timing, and real-time feedback. Progress in 2000 was limited by the ongoing operation of LEP. Following the closure of this machine, 2001 will see a consolidation of the framework established in 2000.

The LHC-CP team also held discussions with the CERN Alarm Team of the SL/CO Group in order to integrate the development of the next CERN alarm system into the scope of the project. A questionnaire is currently being prepared to solicit information from the users, to define the ‘user requirements’ of the alarm system. The team is maintaining close contacts with the slow controls project for the LHC detectors (JCOP). It is also providing technical support for the alarm package using a pilot SCADA project organized by the ST Division and is participating in the middleware project, which will inevitably play an important role in the final alarm solution.

A further development was a pilot study of the future post-mortem needs of the LHC machine. Such a system will provide rapid diagnostics after beam dump or power abort incidents in the LHC. Additionally it will be imperative to monitor the correct functioning of the machine protection equipment. A preliminary survey of the systems required for the post-mortem has started and a catalogue of the necessary data is being compiled. Issues of time stamping and the merging of information from different systems were also addressed.

232 SPS + LEP Division A series of project meetings have been organized since June to facilitate communication between the link- men from each of the groups concerned. The emphasis was on building up the overall knowledge of the participants and on finalizing the mandates for the different project activities. Another important management activity was launched to establish the overall project planning, where the initial focus was on the preparations for the QRL reception tests.

Cavity Technology

LHC Activities

400 MHz Superconducting Cavities

The contract for the welding of the helium vessel on the bare cavities was completed, and all the 21 cavities have now been equipped with such a vessel. Concerning the insulation vessels, eight of them have been received and the remaining number should be delivered by the end of 2001. The first module was assembled and tested at full power and gave a satisfactory performance. Following this testing, the design was improved to arrive at a final configuration. This will be applied to all other modules, while the first module will also be dismantled and re-assembled in the final configuration.

200 MHz Normal Conducting Cavities

Much work has gone into the engineering phase of the development to provide a mechanical design suited to industrial production. The contracts for forging, machining, and welding the eight cavities were placed and production will start in 2001.

LEP Activities

The CT Group gave assistance, when needed, for the maintenance of the cavities in the LEP tunnel, in particular for the HOM couplers and ancillary equipment.

R&D and External Collaborations

Several programmes of R&D were carried out, both inside the group and in collaboration with other laboratories. All these programmes were aimed at improving the performance of superconducting cavities of different shapes, materials, and frequencies.

A reduced-β, four-cell, 352 MHz cavity optimized for particles with β = 0.7 was designed, manufactured, and tested. The excellent result obtained (a Q-factor of more than 109 at 5 MV/m) fulfilled one of the milestones of the Superconducting Proton Linac (SPL) project currently under study at CERN. In addition, a β = 0.8, five-cell cavity, built by modifying a LEP cavity, was tested at full power and in pulsed mode up to 9 MV/m. These results mean that there is now enough confidence to fix the design of the linac in a CERN Report which is to be published shortly.

SPS + LEP Division 233 An agreement was signed with the ESRF (Grenoble) for the installation in their accelerator of a prototype of the SOLEIL cavity. This prototype was successfully produced and tested at CERN using a design from CEA (Saclay). The aim of this collaboration is to demonstrate that intense beams used for the production of synchrotron light can be accelerated by superconducting cavities without introducing harmful instabilities. If successful, this experiment will almost certainly be the trigger for the installation of superconducting RF systems in most of the synchrotron light sources around the world. In view of this, another agreement was signed with CEA (Saclay), PSI (Zurich) and ELETTRA (Trieste), to manufacture and install two third- harmonic superconducting cavities in PSI and ELETTRA. The CT Group will be responsible for the engineering, production, and cold RF tests of these cavities and will assist in their installation in the two accelerators. The design has already been completed and production has started.

An agreement was signed with Cornell University (USA) to produce a 200 MHz superconducting single- cell cavity. The CT Group will again be responsible for the design, engineering, and production, and will participate in the measurements at Cornell. This is the first time that such a low frequency is addressed by a superconducting R&D project. A positive result will give an important boost to the feasibility of muon accelerators. Several technical issues, however, have still to be solved, but a preliminary result is expected by the end of 2001.

The group continued its collaboration with DESY (Hamburg) and CEA (Saclay) to investigate possible improvements in the performance of bulk niobium cavities at 1.3 GHz using a systematic procedure assessed in 1999 which includes electropolishing, heat treatment, and RF testing. The results from a number of cavities demonstrated that, when applied correctly, this ‘recipe’ leads to a performance of 40 ± 3 MV/m. A further effort to ease the implementation of this procedure will be addressed in 2001, and other chemical treatments will also be tested.

A collaboration with the EST/ESM Group was set up to test Nb/Cu 1.3 GHz and 1.5 GHz cavities at high gradients (> 20 MV/m). Four cold tests have been performed so far, with a best result of 27 MV/m at 1.8 K, the first time such a level has been reached.

Several agreements were signed with INFN (Frascati) for the chemical treatment of superconducting cavities for the ISAC accelerator at TRIUMF (Canada), for the detection of gravitational waves, and for the world’s first superconducting RFQ (to be installed in the ALPI accelerator in Legnaro). These last two cavities have already been tested in Italy giving excellent results.

In the frame of the CERN–INFN collaboration for the TRASCO project, the group designed and built the helium vessel for the β = 0.85 cavity that had already been produced and tested at CERN. The group is also responsible for the high-power tests that will be carried out in SM18.

Experimental Areas

West Area

Immediately after the end of the 1999 proton run, the TT60 transfer line to the T1 target and the H3 secondary beam from the T1 target to the West Hall were dismounted to make space for the future TI2 proton

234 SPS + LEP Division injection line to the LHC. A completely new T1 target station was built and the newly designed TT67 and H3 beam lines were installed over a total length of almost a kilometre. The transfer line was moved from the South to the North side of the TT61 tunnel along with all the accompanying infrastructure. The new H3 line was then linked to the existing X5 and X7 test beam lines.

The commissioning of these beam lines went very smoothly and the West Area was fully available for physics on April 30th, before the start of the allocated eight-day commissioning run. Their performance was found to be as expected.

The early start allowed the CMS and LHCb groups to prepare under good conditions for their first test runs using an LHC-type beam (a bunched beam with a 40 MHz structure). As usual, the West Area also provided flexible secondary and tertiary test beams to a number of experiments. In the X5 beam, the main users were COMPASS and the CMS tracking group. In addition, ATLAS, CMS and LHCb took advantage of the accompanying muon fluxes to test their detectors in the Gamma Irradiation Facility (GIF), located at the downstream end of this beam line. On two occasions, the fixed dump between the X5B test zone and the GIF was opened to allow a clean electron beam into the GIF area to calibrate some irradiated crystals from the CMS ECAL. The LHCb group was the main user of the X7 beam, but part of the available beam time was allocated to some smaller tests, in particular AMS, PAMELA, and the traditional summer student workshops.

The X5 beam also housed a new physics experiment during 2000 — WA103. This experiment measures the enhanced photon production in tungsten crystals very precisely, giving information on electron–positron pair production. These measurements are of interest for high-intensity positron sources for future e+e– colliders. The experiment had a very promising physics run in August, from which the first results are expected in the course of 2001.

North Area

At the beginning of SPS operation in 2000, the H2 beam entering hall EHN1 was again adapted to the small experiment, NA59. Using two-stage conversion of 180 GeV/c electrons, tagged photons were produced in a crystal radiator. This was followed by a second, aligned silicon crystal, acting as a ‘quarter-wave plate’, with which the yield of circularly polarized photons could be established. With this experiment still in place, the special LHC-type beam (40 MHz structure) from the SPS was used to produce muons in the H2 line, which were transmitted to the CMS test zone. Subsequently, the standard H2 layout was restored and on two occasions during the year included a CEDAR Cherenkov counter to tag the particle type used by the NA49 experiment. The remainder of the time was used for CMS and, once again, a test of detectors for a ‘recognized’, satellite-borne experiment, ACCESS.

The neighbouring H4 beam was also extensively used by CMS in its electron mode, to test different prototypes of the CMS electromagnetic calorimeter. In addition to CMS, the LHC heavy-ion experiment ALICE was a frequent user of the H4 line for various tests of sub-detector prototypes using hadron beams. The H4 line was also operated in its primary proton beam mode for the investigation of possible luminosity monitors for the LHC.

The main users of the H6 beam continued to be the ATLAS Collaboration for tests of both the electromagnetic and the hadronic endcap liquid argon calorimeters. The ALICE Zero Degree Calorimeter

SPS + LEP Division 235 team also made use of electrons and pions at various energies in this beamline. Other users in H6 included a calorimeter calibration for H1 (HERA), a TRT test run for the AMS space experiment, and several shorter periods for the CERF Radiation Facility, which was operated by the TIS-RP Group.

Apart from a short set-up run for the NA45 experiment, the H8 beam was fully occupied with various ATLAS tests and calibrations for the silicon tracker, silicon pixel, and TRT teams of the inner detectors, the liquid argon barrel electromagnetic calorimeter, the ‘tile’ hadron calorimeter and the muon detector groups. Owing to lack of available test-beam time, two or more ATLAS sub-detector groups often used the beam in parallel. A particularly successful first run with the 40 MHz bunched beam provided useful data to the ATLAS inner detector teams.

In the high-intensity underground area ECN3, NA50 was the first user of the P0 complex. The experiment collected reference data for proton-induced collisions on different target materials. During running with the 40 MHz bunch structure, the beam was successfully exploited for the calibration of the electromagnetic calorimeter with low-intensity electron beams. The last few days of the proton period were used to complete the proton reference data and to prepare for the last heavy-ion run of NA50.

After successful data-taking in 1999 in the quest to precisely measure the ‘direct’ CP-violation parameter, ε′/ε, experiment NA48 suffered from an incident which required the reconstruction of its four large drift chambers, which will not be completed before 2001. In 2000, therefore, the experiment was confined to the detection of neutral-particle, kaon decay modes. The first part of the run was devoted to a measurement of the 0 → π0 0 ‘dilution’ of K S 2 decays by mis-tagged K L events. This required the K12 beam to be set up in its 0 standard, simultaneous beam mode, while ensuring that no protons could reach the K S production target. Time was also devoted to the calibration of the length/energy scale for decays. This was achieved by reconstructing the position of two polyethylene targets introduced into the fiducial volume and illuminated by a beam of π–.

The second half of the run, after the SPS had changed energy from 450 to 400 GeV/c, was used to direct 10 0 0 the proton beam at an intensity of up to 10 protons per pulse onto the K S target. With the K L beam 0 passage ‘plugged’, data to search for rare, neutral K S decays was then accumulated in a dedicated ‘KS High- 0 Intensity’ mode. This mode anticipates the use of the beam in a sensitive search for rare K S decays, which has been approved as experiment NA48/1 in 2002. Studies also proceeded on the improvements required for the beam for this purpose, as well as for the new design required to provide simultaneous K+ and K– beams for the NA48/2 experiment, approved for 2003.

The COMPASS experiment continued its installation in the experimental hall EHN2. Weekends, nights, and some working days were dedicated to detector tests, mostly with muon beams. A small amount of beam time was devoted to calorimeter calibrations with tertiary electron beams, a new type of particle for this beamline.

During the last six-week period of operation, the SPS once again delivered fully stripped lead ions. The momentum was first tuned to 200 GeV/c per unit of charge at the request of NA49, to give an energy per nucleon of 80 GeV, which provided a data-point between the previous energies of 160 GeV and 40 GeV per nucleon. This beam was also used by the other experiments for the setting up of their detectors. Thereafter, the SPS and its beamlines were re-tuned to the standard momentum per charge of 400 GeV/c (160 GeV per

236 SPS + LEP Division nucleon). NA49 also used the lead ions to produce lighter ‘fragments’, especially deuterons, of the same energy per nucleon. With a charge/mass ratio, Z/A = 1/2, this required the H2 beam to be set to a momentum of 320 GeV/c. A comparison of data from this beam with those using 160 GeV protons, allowed the experiment to study effects due to neutrons of the same energy. This beam of ‘fragments’ also gave an occasion to test the response of the ACCESS detectors (mentioned above) to ions heavier than protons, as is found in cosmic radiation. Thanks to the early start with low-energy ion beams, the other experiments (NA45, NA57 and NA50) started off the ion run at nominal energy in good condition, which allowed a maximum of time for the collection of Pb–Pb data.

Emerging Energy Technologies

The EET Group concentrated mainly on the completion of the construction of the neutron Time-Of-Flight (nTOF) facility at CERN. The group has been co-ordinating the construction of the facility with the help of a Technical Board composed of members from several divisions at CERN and, because of its expertise in simulation, has undertaken the calculations necessary for the optimization of the facility.

The nTOF facility is located in the TT2A tunnel under the ISR. It consists of a 40-cm-thick lead target with a cross-section of 80 cm2. 20 GeV/c protons strike the target and produce an intense neutron beam via the spallation process. One bunch of 7 × 1012 protons at 20 GeV/c will produce ~ 2 × 1015 neutrons over 2π. The target is water-cooled, and this cooling also acts as a neutron moderator. The resulting neutron beam then travels almost 185 m inside a vacuum chamber before being detected. Monitoring the arrival of the neutrons gives rise to a time spectrum that depends on the neutron kinetic energy. This allows for an unprecedented energy resolution in the measurement of neutron-induced reaction cross-sections.

The commissioning phase of the nTOF facility started on 8 November 2000, when the first protons were sent from the PS. With an intensity of ~ 1011 protons per cycle on the nTOF target, an intense neutron beam was produced for the first time at CERN. Soon after the start of commissioning, the EET Group was able to measure the neutron spectrum at a distance of 172.5 m from the target using small neutron counters. By inserting a gold foil in front of these counters, the 197Au capture resonance at 60.3 eV could be measured with a precision of 1.6 × 10–3. The intensity could be varied between 1 × 1011 and 4 × 1011 protons per bunch with up to three bunches per PS supercycle. At a later stage the nominal intensity of 7 × 1012 protons per bunch with four bunches per PS supercycle was reached for a very short time. Temperature measurements of the target were taken at this nominal intensity, and these agreed with the numerical simulations performed. The commissioning phase continued until the PS run finished at the end of November. During this phase, two additional collimators were inserted into the neutron beam line. Though very preliminary, these first results indicate that the facility behaves as expected and that the observed radiation levels are acceptable. In spring 2001, a few additional measurements will conclude the commissioning.

The goal of this facility is to obtain a more precise experimental determination of neutron-induced reaction cross-sections for isotopes of interest in the fields of nuclear astrophysics, dosimetry and nuclear technology, and fundamental nuclear physics. It is also of importance in the design of accelerator-driven systems for the transmutation of nuclear waste and energy production. The long flight path of ~ 185 m in vacuum allows an energy resolution of 10–4 to 10–3 from 1 eV to 1 MeV. This resolution combined with the high neutron intensity available makes this facility ideal for the measurement of unresolved resonances in the energy range below 1 MeV.

SPS + LEP Division 237 The nTOF facility is currently the most powerful neutron source for the direct measurement of neutron cross-sections in the energy range from 1 eV to 250 MeV. From 2001 onwards four proton bunches with a nominal intensity of 7 × 1012 protons per bunch are expected per PS supercycle of 14.4 seconds.

In the first half of 2001 the nTOF Collaboration, which consists of almost 150 scientists from 40 institutes, will start its scientific programme by precisely calibrating the neutron flux spectrum. From the series of proposals submitted for approval to the ISOLDE and nTOF Committee (INTC), it can be inferred that nTOF will be the basis of intense scientific activity over the coming years.

SPS/LHC Radio Frequency

SPS Radio Frequency

Proton, Lepton and Ion Operation

The 1999/2000 shutdown period ended in week 8 and was followed by a cold check-out period of approximately four weeks. Week 13 was used to set up the 3.5 GeV to 22 GeV lepton acceleration ready for LEP operation, which started in week 14.

Protons were available on an economy cycle in weeks 14 and 15 for MD purposes. Setting-up for proton operation started after Easter in week 17 and the initial part of the proton period was assigned to low-intensity LHC test beams, i.e. a 26–450 GeV cycle with 25 ns bunch spacing, for tests of LHC detector electronics in the experimental areas. These tests terminated in week 21 when the changeover to standard fixed-target physics was made (two batches accelerated from 14 GeV to 450 GeV). Proton physics then continued until week 36. The last seven weeks of operation (weeks 38 to 44) were dedicated to lead-ion physics following a week of setting up with ions (week 37). LEP operation continued throughout this period until November 2nd.

During the whole year, a test cycle (P2) was available for machine development (MD) studies using many different beams. Transfer to LEP was possible at 20 GeV during long MDs with LHC beams. With high- intensity LHC beams strong coupling was used on the 352 MHz superconducting cavities. The 200 MHz SWC system then had to work at its maximum capability to compensate the consequent lack of voltage from the SC system.

‘Piquet’ services were provided as usual for rapid fault analysis and intervention on the transverse damper, the beam-control RF systems, and the different high-power systems. As is the case every year, much effort went into maintenance work to ensure reliable operation of the SPS RF power plants. These plants consist of several types of cavities and amplifiers, namely: travelling-wave cavities; standing-wave and superconducting cavities; ~ 150 tetrode power amplifiers (ranging from 1 kW to 140 kW and 100 MHz to 350 MHz); eight klystron amplifiers (each 58 kW, 800 MHz). Also included in the maintenance effort was the auxiliary equipment, such as the high-voltage power converters, regulated power supplies, air and water cooling systems, interlocks and controls. All RF power plants achieved very reliable operation during 2000. The 100 MHz and 350 MHz power systems worked without failure during the whole run.

238 SPS + LEP Division The prototype high-voltage thyristor crowbar systems were delivered and successfully tested at CERN. These devices will replace the ignitrons (containing mercury) of all HV power converters of the SPS RF power plants. The series production is also finished and installation has started.

A major project that was defined and planned in detail during 2000 and started at the beginning of the shutdown in December 2000, is the refurbishing of the Faraday cage. The Faraday cage which houses and protects all the electronics of the RF beam control systems for the different modes of operation of the SPS is now 25 years old and in urgent need of repair. These repairs entail the complete emptying of the Faraday cage and replacement of the cooling system, flooring, and all cabling. The removal of the lepton equipment and the introduction of new electronics for operation of the SPS as LHC injector and the CNGS project also imply major changes in the Faraday cage. Six months are required to do the work, which will last the length of the long shutdown associated with the closure of LEP. The LEP closure also implies a significant number of changes to the SPS itself, with all lepton RF equipment being removed from the ring and the associated equipment in many buildings being dismantled. This work will again take place during the long 2000/2001 shutdown.

SPS as LHC Injector

The physics period with low-intensity LHC-type beam, accelerated from 26 GeV and extracted to the experimental areas at 450 GeV, was a good initial test for the first prototype part of the beam-control systems for acceleration and synchronization before transfer. The small jitter in the arrival time of the bunches as seen by the experiments was very encouraging.

Machine development (MD) studies concentrated this year on the production of beams for the LHC. Experience with this type of beam has led to various hardware improvements of the low-level electronics of the beam-control and transverse damper and in the power amplifier chains. Studies also continued on collective effects in the SPS. The shielding of the MST magnetic septa, which was believed to be the major source of 400 MHz impedance in the machine, did not give the expected impedance reduction in measurements with the beam. A search was made for further possible sources in the laboratory and by using numerical simulations. It is now believed that the kicker magnets (MKE and MKP) also have significant impedance in this frequency range and should be shielded when possible. A series of reference measurements were made on the beam by inspecting both global effects and effects at particular frequencies to prepare for the major changes that will take place during the next long shutdown with the removal of lepton equipment and the shielding of the pumping ports.

To reduce the impedance seen by the beam over the bandwidth of the travelling-wave cavities a feed- forward and feedback are being applied. Feed-forward electronics incorporating new digital filters is now available for all cavities, has been successfully tested, and is seen to track well during the acceleration cycle with the new RF phase compensation. A new wide-band feedback system is now also available for one cavity — the full system will be available next year. Significant improvements have already been seen for the problem of beam-loading on the LHC beams. Tests have shown that the performance of the feedback and feed-forward are now limited by the power amplifier chains, in particular the frequency response of the Siemens amplifiers and the amplitude linearity of the transistor amplifiers in the Philips amplifier. Methods of improving these are currently being studied.

SPS + LEP Division 239 High-power RF tests on the new main couplers for the 200 MHz travelling-wave cavities (TWC) continued at the beginning of the year, making use of one 1 MW, TWC amplifier. These couplers are fitted with modified high-power ceramic klystron windows (similar to those of the LEP klystrons). Two different prototype windows from two manufacturers were mounted in the test set-up. Unfortunately, one window failed due to multipactoring at high levels of RF power. The test set-up was then equipped with two windows from the remaining manufacturer, and high-power tests restarted after the physics run at the end of the year. After the usual RF conditioning, full power was reached for both CW and pulsed operation. The first of the four TWCs is currently being equipped with these new couplers.

For the main beam control system, a new synchronization loop amplifier was developed with a time constant that follows the synchrotron frequency variation to improve the loop stability during acceleration. Measurements were made and modifications introduced to reduce the noise in the different loops and to improve the lifetime of the beam on the long 26 GeV plateau. The 800 MHz system will be used to provide Landau damping for intense beams and various electronics modules for the cavity-control loops were developed and tested to ease operation with the LHC beams.

One of the two 800 MHz accelerating cavities (using four klystrons) was operational during the whole year. The cooling water circuit for the klystrons has, however, been improved to permit reliable operation with both cavities. The main transformers and the thyristor regulators of the high voltage DC power converters will also have to be replaced.

On the instrumentation side, software for analysing bunch profile measurements to obtain beam parameters was further extended, and a device to observe the peak line density of a given single bunch in a batch was developed. A prototype LHC wide-band pick-up was installed in the SPS and tested with the LHC beams.

The electron cloud effect, first observed in 1999, distorted the signals from the pick-ups of the transverse damper system. New electronics working at 120 MHz, built to combat this problem, was successfully commissioned during the year. The last two power amplifiers with high-bandwidth capability were also installed and used in all modes of operation. While the high-voltage power supplies have the capacity necessary for these new amplifiers, they are old and two failed during the year. It was, however, possible to find temporary solutions for operating the damper, and physics was unaffected. New power supplies have been ordered and will be installed in 2001. A new 12-bit digital filter for closed orbit rejection, offering adjustable delay and operating at 80 MHz, was developed together with various electronic modules to transmit the RF reference signals from BA3 to BA2 to synchronize the clock of the transverse damper. Two complete chassis have been built and are now operational.

A study of a persistent problem with the beam when operated close to the 0.5 non-integer tune value with the damper at high gain has shown that one solution is to re-locate one of the pairs of vertical dampers. They will then have sufficient betatron phase shift between them to alleviate this problem. This change will be carried out during the next shutdown.

240 SPS + LEP Division LHC Activities

The RF systems for the LHC consist of 16 superconducting (SC) 400 MHz cavities, 8 normal-conducting 200 MHz cavities, and 12 transverse kickers. The production of the various components for the 400 MHz RF acceleration cavity modules is now well under way and the first complete module of four cavities was tested at both low and high power in December 2000.

Although prototype variable couplers were successfully tested at high power on a SC bi-module, technical problems occurred during the manufacturing of the pre-series, with cracks appearing in some of the ceramic windows. Despite this problem, the first LHC module (four SC cavities) has been equipped with four couplers, permitting high power testing of the module and its components. One of the couplers has been tested up to 200 kW CW and 300 kW pulsed power (corresponding to equivalent peak power levels of 800 kW and 1200 kW respectively, due to the full reflection at the cavity input). It was also possible to condition this coupler at any phase, without instabilities, by simply de-tuning the cavity. This is an important achievement, since it permits complete conditioning of the LHC modules without beam. Unfortunately, after warming up the module it became evident that one of the four couplers (but not the one tested at very high power levels!) had a vacuum leak, probably due to the above-mentioned cracks in the ceramic window. For the series production of the windows the design has been slightly modified and the tooling improved to avoid these cracks during manufacturing. The first windows of the series production should be available in March 2001. All other parts for the series production of the couplers have been ordered and most of them have already been delivered.

The specification of the klystrons for the 400 MHz power amplifiers was sent out to industry (three firms) for tender, with the contract agreed at the CERN Finance Committee in December 2000. The specification for the circulators is finished and the call for tender has been sent out. This is expected to be presented to the Finance Committee in March 2001.

The 200 MHz capture system was defined during this year. Eight cavities are to be connected to their power plants with coaxial lines (230 mm in diameter). No extra civil engineering is needed. A four-amplifier connection (using tetrode amplifiers from the SWC system) with circulator and a more powerful coupler (with compensated loop and adjustable coupling) will be used. The RF calculations for the power coupler were completed and the design of a low power model (required for cavity tuning and measurement of higher order modes) is practically finished. Parts of this model are already being manufactured and the assembly is expected to be ready in April 2001.

The design of the 200 MHz power plants (40 tetrodes of 60 kW each) was finalized. Market surveys for the power combiners and the coaxial lines were also prepared, and the series production of the cavities launched. Low-power tests will be performed on the first cavity of the series in the factory and an extensive test procedure has been defined.

The first version of the prototype kicker for the transverse damper system was delivered in January 2000 from JINR (Dubna) together with a two-tetrode version of the power amplifier. Successful tests were made on the ensemble with nominal high voltage. The response is now resonance-free to 20 MHz. The rise in temperature of the kicker electrodes due to the heat deposition from the electron cloud phenomenon (laboratory simulation) was measured on this kicker prototype. Although the temperature rise was within

SPS + LEP Division 241 acceptable limits, the heat loss paths via the ceramic supports and electrical feedthroughs are not well defined. This is under study to confirm whether the design is acceptable. Samples of the materials used in the kicker are being tested for conformity at CERN. It is foreseen that the remaining undecided points will be clarified such that a pre-series production can be launched at the beginning of 2001.

The installation of all RF systems in the machine tunnel and the klystron gallery is difficult because of the restricted space available. Much progress has been made in the design during this year, and the layout is nearly finalized. Systems integration in 3D has also started. The services for all RF systems have been defined. The total installed RF power is 8160 kW. The most critical point is the ventilation of the RF zones in the klystron tunnel. A total of 190 kW is dissipated into air. It will be treated by dedicated ventilation systems for the klystrons, the 200 MHz power plants, and six different rows of control racks. Layouts are ready for approval.

Because of the restricted space in the tunnel, much of the RF equipment has to be installed in the surface building SR4 where 300 m2 has been reserved for the RF Group. Design has started for the layout of this area, which includes a new Faraday cage for the RF controls.

The RF test area in Building SA2 will continue to be used by the RF Group. One cavity test bunker will be dismounted, leaving one operational, and handed over to an experimental group together with the remainder of the building. A new door has been built for access to the RF test area.

Studies on the longitudinal beam dynamics in the LHC have enabled the requirements for the HOM damping in the cavities to be determined. The RF and beam parameters of the nominal beam have also been defined through the cycle to optimize beam stability. The emittance of the beam must be increased from 0.7 eV at low energy in proportion to the square root of energy. Methods to do this are under study. Simulations of the LHC RF system with beam have continued with the existing program being improved for cases that are more complex. A preliminary definition has been made of the RF requirements for the slow timing system, the function generators, and the RF signals for post-mortem.

LEP Radio Frequency

The remaining LEP2 spare couplers were completed, RF conditioned, and power tested. The conditioning stand for LEP2 couplers is to be kept operational to permit high-power RF tests on new types of conductors with low secondary electron emission.

Other Activities

A study was undertaken for the SPL Project, in collaboration with PS Division, simulating the beam motion in the superconducting cavities of a proton linac in the presence of microphonics and Lorentz detuning. A new computer program was developed for this purpose.

242 SPS + LEP Division LEP Radio Frequency

LEP RF Exploitation

New Cavities

During the 1999/2000 winter shutdown, eight copper cavities were re-installed in space liberated by the removal of bunch train separators. With this, the total number of copper cavities became 56 and the number of superconducting (SC) cavities in LEP remained at 288. However, one superconducting module installed during the 1998/1999 shutdown, which had reached 7 MV/m in the test string, could only be conditioned to 5.5 MV/m in LEP in 1999. This module was consequently removed from LEP in the 1999/2000 shutdown for the water rinsing of two cavities. During this process, it turned out that one cavity had to be completely re- coated. The module was nevertheless re-installed in LEP before the 2000 start-up.

System Improvements

Modifications were carried out on the water-cooled RF absorbers of the waveguide system in the superconducting RF units. Asymmetric reflections from detuned cavities can produce up to 300 kW dissipation in the water loads on the first magic tee. This leads to an excessive temperature rise in these loads, rated at 100 kW, which causes the polystyrene coaxial insulator at the input end to melt. Loads in 31 SC half-units were fitted with Teflon insulators and the remaining five half-units were fitted with 300 kW loads from unused copper units. In some half-units the 300 kW circulator loads were replaced by a longer 6 m version with increased water flow. This improved the temperature stability and allowed a better control of low-frequency oscillations caused by reflections back to the klystron from the circulator.

The programme to reduce the field spread between individual cavities, started in 1999, was continued. This involved adjustments to the waveguide system and the optimization of the method for setting the tuning set points, which is particularly sensitive at injection. Vector sum feedback had been used with increasing success in 1999. However, as in previous years, installation, set-up and testing times were very limited in 2000 and vector sum feedback was set up only in units especially prone to low-frequency oscillations.

The Active Damping System

Ponderomotive oscillations of the cavities had been a problem during previous years. In 1999 an active damping system was developed using the existing tuning hardware. This system was completed in 2000, and in June it was operational for all Nb/Cu SC cavities, except for units 232 and 233, where important cryogenic vibrations made the setting up of this system impossible. This exception was also true for all the solid Nb cavities, which run at lower accelerating gradients. There were, however, some cavities where the oscillations could not be damped. This was explained by the presence of two mechanical cavity resonances, close together in frequency and with similar amplitudes. An alternative solution based on a compensating filter proposed by specialists at Supelec (Paris) was also followed up. The required fourth-order filter was successfully implemented in a DSP and effective damping could be obtained in most, but not all, cavities. The use of this filter for RF modules was tried where cryogenic oscillations prevented the use of the above-mentioned analog

SPS + LEP Division 243 system. It was confirmed, however, that simple scaling of the characteristics did not work for all cavities and that measurement and recalculation was required.

GPS Based Logging

A serious problem for LEP operation in previous years had been the extreme difficulty in separating the cause and effect of rapid beam loss, since beam loss itself can cause RF units to trip and RF trips can cause beam loss. In 2000, a fast ‘post-mortem’ diagnostics system was therefore installed to allow the precise time- stamping of RF unit trips and beam loss. For this, the existing LEP GPS system was extended into the klystron galleries to synchronize local DSP based acquisition and event recording units in each RF sector. An overall application driven by the LEPExec armed all DSP units at the start of each fill and retrieved and sorted local event table data at the end. Results of the overall trip sequence and beam loss could be displayed and were automatically stored in the operations database on a fill-by-fill basis. These were regularly compared with alarm system and machine data to track systematic problems and to optimize the maximum operating levels of the individual RF units. The system proved to be an extremely important diagnostic tool, which helped to considerably improve the reliability of LEP operation in 2000.

RF Controls

Most of the reliability problems with the hardware of the RF controls system had already been eliminated in previous years. However, for this last year of LEP operation, certain rectifier diodes were upgraded in all 288 cavity tuning power supply units by the SL/PO Group. This eliminated the breakdown problems these units had previously suffered from. Some improvements were also made to the software of the RF system in order to facilitate reaching and maintaining the maximum RF voltage with maximum reliability. These included the automatic raising of selected RF units from safe levels to their maximum levels and refinements in the method of controlling the cavity tuning set points to minimize ponderomotive oscillations during the coast.

RF System Operation

After the 1999/2000 winter shutdown the superconducting cavities were conditioned to give an average maximum gradient of 7.5 MV/m for the Nb/Cu cavities and 5 MV/m for the 16 bulk Nb cavities. However, stable operation with beam for physics required staying below these maximum values and an RF voltage margin of two klystrons was typically required. Running with reduced margin allowed higher energies, but increased the risk of beam loss due to RF trips. For a given energy a compromise had to be found between RF margin, trip rate, and beam current. Increasing the beam energy during the fill via mini-ramps proved to be a very good compromise solution, since the increased risk of losing the beam was offset by the fact that the RF stability increased with decreasing beam current. In this mode of operation, fills started with a margin of two klystrons to reduce the risk of losing the beam at high currents. This was followed by a margin of one klystron at a higher beam energy, and then finally with no margin where the energy raised to its maximum and an RF trip led to the loss of beam.

Physics in 2000 started at 100 GeV. During operation it was then possible to gradually increase the accelerating fields in some units. Once stable running was achieved at this higher gradient, the energy was

244 SPS + LEP Division increased. With this strategy and the mini-ramping scheme, the beam energy was increased to 101 GeV, then 102 GeV, and finally to more than 104 GeV. The total voltage available at this energy was about 3650 MV.

The overall operational reliability was very good considering the size and complexity of the system and the mode of operation, which was constantly pushing the system to its limits. In total, five cavities degraded in their performance and had to run at reduced gradients or fully detuned. The performance of three of these was fully recovered in situ by conditioning and pulse processing, while the others remained operational at reduced gradients. One cavity was fully detuned all year because of problems with the fundamental mode rejection filter in the HOM coupler.

The maximum beam current was limited to 5.3 mA during the year because of problems with HOM connector cables on the bulk Nb modules. Some of these RF connectors were found corroded or even burnt, which strongly affected or even prevented the extraction of HOM power in these cavities. This problem was traced to the over-cooling of the HOM cables, leading to condensation and then arcing in the external connectors. One of the bulk Nb modules even developed a vacuum leak from the insulation vacuum of the cryostat, due to the destruction of the RF feedthrough by arcing.

Four klystrons and three circulators had to be replaced during the year. In the waveguide distribution system, a few coaxial components on the high-power RF absorbers also had to be replaced because of thermal overload. Two sections of full-height waveguide of about 10 m were damaged by arcing, believed to have been caused by trapped higher order modes, and were replaced.

Feedback Systems

The transverse feedback system was fully operational in 2000, but was not required on account of the relatively low bunch currents.

The longitudinal feedback system was used during the whole running period and worked reliably at power levels of about 100 kW, although the tuning system of the cavities was inhibited because of synchrotron radiation damage of the cables.

Work for the LHC RF System

Specifications for the LHC 400 MHz klystrons and circulators were established and sent to European industry together with a ‘Call for Tenders’. The contract for the development, manufacturing, and testing of all 400 MHz, 300 kW klystrons required in the LHC was subsequently placed. The decision for the circulators will be taken in March 2001. The tunnel layout of the 400 MHz high-power RF system (klystron with driver amplifier, circulator, termination load, and waveguide components) was also finalized.

The development of a computer-based measurement system was launched, which will allow the quantitative measurement of the harmonic content of all possible propagation modes in the waveguide output line of the LHC klystrons.

SPS + LEP Division 245 Main Rings

SPS Activities

The main activity during the 1999/2000 shutdown was the installation of the pumping port shielding. Only the MBA/MBB type of shield was available and these were installed on a total of 74 magnets. The remainder of the programme will be completed during the long shutdown in 2001. Another aspect of the impedance reduction programme was the installation of RF shielding in the extraction equipment. The new graphite cored beam dump was also installed in the machine during this shutdown.

In preparation for the new transfer lines to the LHC, the T1 target and associated beam line were displaced to make room for TI2. Following the completion of tunnelling operations towards the SPS of the TI8/TT40 transfer line, a shield wall had to be installed to allow civil engineering work to continue once the machine had re-started. Before the tunnel was closed off, strong air currents caused by convection carried large quantities of dust into ECA4 contaminating the RF equipment installed there. A crash programme to clean the area was instigated and the equipment was ready for operation before the start of the SPS run.

A new radiation test facility for electronics for the LHC was created in BA80 and TCC2. This facility allows the testing of components and modules destined for use in the LHC tunnel in a radiation environment that is very similar to what is expected for the LHC arcs.

In July a new convention was signed with the French Authorities which classified the LHC and SPS (including the CNGS project) as French Nuclear Installations (Installations Nucléaire de Base, INB). The new convention came into effect two months after its signature. In its draft form the new convention only concerned the LHC, but CERN was asked to include the SPS in the definitive version. As a result, it was necessary to implement new procedures to allow the full traceability of materials from the SPS during the long shutdown in 2001 and to establish a radiological zoning plan. Preliminary systems were in place at the start of the 2001 shutdown and it is planned to implement a more complete system for the 2001/2002 shutdown.

Tunnel movements due to the various civil engineering works were observed as foreseen during the year 2000. Excavation of the ATLAS USA15 cavern caused machine elements in sextant 6 just upstream of the west extraction channel (6-12 to 6-16) to subside by up to 4.5 mm. A movement of similar magnitude was also observed in the adjacent portion of the TI12 LEP transfer line. These elements were realigned at the beginning of the year to include an extra 1.5 mm in anticipation of further displacement. During operation, the same zones moved again, this time due to the UX15 cavern excavation. A further 5 mm subsidence was observed together with a radial component of up to 7 mm, the realignment of which was carried out during the end-of- year shutdown. Adjacent to the TI8 junction, the horizontal diameter of the SPS tunnel section was observed to have increased by up to 20 mm! The position of the machine elements however, remained within acceptable limits. TI2 passing beneath TT10 had no measurable effect.

LEP Activities

At the LEP sites there was a continual effort to maintain the infrastructure. The MR Group also played a significant role for the visits service until the end of the LEP run when all visits were terminated.

246 SPS + LEP Division During the annual shutdown, the majority of the work was associated with the final preparations to run the machine at the maximum energy. Eight copper RF cavities were re-installed around points 2 and 6, in space liberated by the removal of electrostatic separators. A number of interventions were made on equipment which had been damaged by the synchrotron radiation and some more shielding was installed to protect equipment from this radiation.

LHC civil engineering continued to have an impact around the LEP sites, most importantly in the machine tunnel at point 1 where a realignment was necessary. From mid summer there was a continuous upward movement of the tunnel floor with a maximum integrated movement of around 10 mm. There was water infiltration in the PM15 shaft and there were problems with the vertical alignment of the lift shaft at point 5 where significant lateral movements had occurred. Since there were delays in the excavation of the pillar and caverns at point 5, no tunnel movements were observed.

The LEP sites were considerably modified by the LHC construction programme. The space available at point 8 was significantly reduced and it was therefore necessary to increase the parking areas outside the site. This was done with reluctance, and will involve the replanting of trees following the end of the civil works. At other sites, modifications were made to the access roads to facilitate the simultaneous dismantling of the machine and experiments, and LHC construction.

LEP Dismantling

Activities concerning the LEP Dismantling Project intensified during the year and dismantling finally started immediately after the closure of LEP in November. In the early part of the year contracts were prepared for the execution of traceability activities, the employment of radiation protection technicians, and for the sale of scrap materials. Further man-years were devoted to the preparation of documentation for the French Authorities. The infrastructure for dismantling, including the transit zone and storage facilities, was also prepared. Owing to the lack of storage space caused by the delay in the construction of a new radioactive storage facility, the SL storage areas were rationalized so that maximum use could be made of the existing buildings. This involved disposing of large quantities of non-radioactive equipment.

The traceability system was conceived and implemented in the MR Group. Design work was completed during the year and the new software procedures were tested and put into operation. Hardware procurement was completed and the equipment was installed before the end of the LEP run. Around twenty people are involved in the execution of this task, which involves recording movements, maintaining the equipment and database, and supervision and quality control.

The radioactive waste storage facilities managed by TIS/RP in the ISR were insufficient for the requirements of LEP dismantling and the SPS upgrade (SLI Project), and consequently a crash renovation programme was instigated and managed by MR. Parts of the ISR tunnel were cleared of stored equipment, and water leaks and structural weaknesses were repaired. Separate areas were created for the storage of radioactive waste from the SPS and LEP, and further areas were prepared for equipment from LEP destined for future use. In order to minimize radiation doses in the SPS waste area the overhead crane was refurbished. A total surface area of ~ 3500 m2 was prepared with approximately 40% of this destined for radioactive waste storage.

SPS + LEP Division 247 An Executive Committee for the dismantling project was formed and held regular meetings to prepare for the dismantling and to follow progress once it had started. Courses were also organized for the safety training of personnel working underground during the dismantling. Over 2000 people were trained by MR staff. The dismantling course has since been added as an option to the training given by the Fire Brigade to all staff who will work underground.

The extension of the LEP run in 2000 and changes to the civil engineering planning for the LHC required changes to be made to the LEP Dismantling planning. The project will now finish at the end of April 2002. The extension of the work is to facilitate an earlier access by the civil engineering contractor to the area around the junction of TI8 with the main tunnel. The LEP machine equipment which is between this junction and point 1 will not be removed until after the completion of the civil works, which implies starting its removal in November 2001 after the completion of all other dismantling activities.

Final approval from the French Authorities for the dismantling of LEP was obtained in November just before the work was due to commence. The initial phase involved making the areas safe by cutting electrical supplies, removing fluids and dangerous gases, venting vacuum, etc. Following this, the teams responsible for the different activities in the tunnel had training specific to their particular tasks before starting the full dismantling programme. On the surface the weigh-bridge and radiation detectors were commissioned and the procedures for the removal, sale, and storage of materials were put into operation.

Resistive Magnets

PS Complex

Eight magnetic elements were completely overhauled during the year, and the insulation of the thermoswitches which protect the coils of the main PS magnets were reinforced. The new style of operation of the PS machine was found to give tighter constraints on the figure of eight loops. It was therefore decided that their accessible bolts will be checked and tightened during each winter shutdown. Leaks were observed in some enlarged quadrupoles due to the ageing of the magnets. These were designed to be used in DC mode but are now operated in pulsed mode for the Antiproton Decelerator (AD). In order to avoid further problems, studies have been undertaken to find solutions that can be implemented in situ to improve all the magnets.

The thick septum magnets used in the slow extraction of the PS beam to the experimental areas of the East Hall will have to be re-built owing to the high radiation doses they have received during their operation. The system insulating the current-carrying parts from the cooling circuits has therefore been re-designed using novel radiation-hard materials. Three of these magnets are currently being built by industry along with two fast, pulsed magnets as spares for the ones currently used during the extraction bump in the PS. Spare coils for corrector magnets in the PS and its injection line are also being built.

The SPS Main Ring Magnets

Consolidation and preventive maintenance for the SPS magnet system are on-going. Fourteen of the main magnets have been rebuilt with new coils. Four MBB magnets failed during SPS operation, two with vacuum

248 SPS + LEP Division chamber problems and two with magnet coil problems. Eleven of the main dipoles were exchanged to meet the more stringent requirements for the positioning of the vacuum chambers put forward by the ‘Pumping Port Shielding Project’. Eight of the lattice quadrupoles showed strong coil movements due to radiation damage, and were replaced. Seven MBB coils and eighteen QF/D coils had their insulation renewed by industry. Eleven bumper and correction dipoles have been overhauled and prepared for installation in LSS4. In order to create space for the new ejection in ECX4 several solutions for displacing the bus-bars of the main dipole system have been studied. Models have been built and special tools developed.

SPS Transfer Line Magnets

Twenty magnets were refurbished and twenty-one repaired and tested in the CERN workshop during the year. Four QNL and one QTA beam transfer quadrupoles were completely rebuilt by industry. A contract was also placed for the refurbishment of QNL and QTL/A coils. The copper for a series of new QTL coils was ordered. An increasing number of beam transfer quadrupoles are showing radiation damage, especially in the secondary beam lines. A bigger contract for rebuilding radioactive QNL, QWL, QTL and QTA quadrupoles is urgently needed and a technical specification for tendering is under preparation. A gap measuring device for QNL quadrupoles has been adapted for QTA quadrupoles, while electronics modules for zero magnetic field hall probes were implemented and installed in the West and North areas. Four MBHC dipoles for the TT40 transfer line are currently also being built by industry.

LHC Beam Transfer Lines

In total, 232 MBI and 109 MQI magnets have so far been built and delivered by BINP (Novosibirsk). A problem stemming from new stamping tools was discovered early in the year, which resulted in the total halt of production of MBI dipoles from April to July, and will lead to the extension of the delivery programme until summer 2001.

A contract for the fabrication of 1610 SPS-type magnet jacks has also been placed with BINP and 10 prototype jacks have already been delivered. Copper for 10 MBI spare coils and MBI bus bars was ordered during the year.

A software program using LabView was developed for MBI and MQI magnet power tests, and a total of 73 MBI dipoles and 40 MQI quadrupoles have so far been tested. Gap measurements have been carried out on 48 MQI quadrupoles and the coil displacement has been investigated and measured on 15 magnets. A first implementation of a test bench for thermoswitches was also carried out during the year.

LEP Magnets

During 2000 the LEP magnet system was still remarkably stable, despite the effects of the ever-increasing synchrotron radiation. Some problems were seen on MQA quadrupoles, where the insulation resistance of vetronite plates degraded by orders of magnitudes owing to this radiation. Corresponding preventive maintenance activities were considered in view of a possible running of LEP in 2001. After the LEP closure, the dismantling of the magnet system was started in December. During the year, the dismantling method had

SPS + LEP Division 249 been studied and the necessary tooling had been procured. A detailed plan was also made for the dismantling of the magnet system.

LEP Energy Calibration

In the framework of the LEP Energy Calibration, considerable effort was once more devoted to the installation, follow-up and data analysis of the NMR probes. The increase in LEP energy increased the synchrotron radiation damage on the 24 NMR probes installed on the main dipoles. NMR lifetime was seen to decrease as the LEP energy increased. In spite of all the lead shielding, the NMR probes had to be replaced eight times during the LEP run in 2000. This can be compared to the 1999 LEP run where they were replaced four times, and the 1998 LEP run where they were replaced only once. In the framework of the NMR studies and improvements against synchrotron radiation damage, two NMR probes having a water bulb sample tip were installed in LEP. First results indicate that this type of NMR probe shows a more consistent behaviour towards radiation damage than the conventional rubber sample type. The amplitude of the resonance signal was, however, lower than for conventional probes, thus increasing the value of the minimum measurable magnetic field. These studies were conducted in collaboration with Metrolab in Geneva. The Flux-Loop system became increasingly unreliable on account of both synchrotron radiation damage and the ageing of the concrete dipoles.

LEP Magnet Control

There was a continuous follow-up of the LEP reference magnet, the online monitoring of the main dipoles field, the control for the girders of the experimental insertions, the low-beta superconduncting quadrupoles and the quench recorders of all four LEP IPs. A total of 58 quenches occurred during the LEP run in 2000. The increased unreliability of the thermoswitches caused by the increase in synchrotron radiation damage had to be coped with throughout the year.

LHC Cleaning Insertion Magnets

The MQW twin-aperture quadrupoles for the LHC cleaning insertions form part of the Canadian contribution to the LHC. A pre-series magnet is currently under construction. Problems at the manufacturer, Alstom (Canada), have led to delays, but these do not yet have any influence on the overall LHC schedule. The design modifications that were found necessary after the measurement of the prototype have now been implemented. A magnetic measurement set-up using a rotating coil was tested with the prototype. The raw materials for the series production have been procured, and three-dimensional field models have been implemented to help in interpreting the magnetic measurements and to study the effects of the end shims.

The resistive dipole magnets for the LHC cleaning insertions will be built in collaboration with BINP (Novosibirsk). The magnetic design and the technical specification of the MBW separation dipoles have already been completed and the preparation for the construction of a prototype magnet is under way. The magnetic design of the MCBW correction dipoles and the MBXW separation dipoles is well advanced and their functional specifications have been established.

250 SPS + LEP Division LHC Steel Septum Magnets

For the LHC injection and beam dumping systems, a total of 45 steel septum magnets are required. The magnets will be built in collaboration with IHEP (Protvino). During 2000 one MSIB prototype and one MSDC prototype were built. The mechanical properties of the yokes fulfil the specification, and the coils built so far are fully satisfactory. Measurements of the magnetic properties of the assembled magnets are currently being carried out and analysed. All the raw materials have been procured and delivered to Protvino; however, progress is slower than foreseen, but is not yet affecting the overall LHC schedule.

CNGS Magnets

For the TT41 transfer line from the SPS to the CNGS target, 78 MBG dipoles and 23 QTG quadrupoles are required. The magnets will be built in collaboration with BINP (Novosibirsk) and are funded by a special German contribution made available via DESY (Hamburg). A three-party ‘Memorandum of Understanding’ defining the roles of the partners has been signed by CERN, DESY and BINP. The magnetic design is well advanced and the functional specifications have been established. Procurement of the raw materials required for the prototypes is under way.

Operations

SPS Operations

Proton Run

The SPS provided protons for physics from 2 May until 9 September 2000. The proton run during the year was divided into four different periods of operation. A first short period (2–12 May) was dedicated to commissioning of the new transfer line (TT67) to the new target station T1, using the 450 GeV cycle with a 2.3 second flat-top. The machine then switched to a special mode of operation using the LHC injection cycle and an LHC-type beam for physics. Eighty-four bunches spaced by 25 ns were accelerated up to 450 GeV and extracted to all targets during a 2 second slow spill, during which the RF was kept on to preserve the bunch structure. The total intensity in the SPS was kept at 3 × 1012, which was below the electron cloud threshold. This period was requested by the future LHC experiments in order to commission their timing and trigger systems. From 26 May to 12 July the normal fixed-target cycle (450 GeV, 2.3 second flat-top) was used with a moderate intensity of 2.5 × 1013 protons/cycle. Operation was then switched to a 400 GeV cycle with a 3.2 second flat-top, with the experiments preferring the increased duty cycle over the maximum energy. The average intensity during this run was increased to 3.1 × 1012 protons/cycle, and the cycle was kept until the end of the proton run on 9 September.

The number of hours available for physics was 2556 compared to the scheduled 2896 hours. This gives a total SPS efficiency of 88.3%, again a new overall SPS record. The major breakdowns that occurred during the proton period are listed below.

– BB3 transformer explosion and subsequent fire, 7 May

SPS + LEP Division 251 – Vacuum leaks in two main dipoles, 8–9 May

– Exchange of ZS1 in LSS2, 14–15 June (Confusion about the interpretation of the radiation measurement cost 40 hours)

– Compensator failure due to a fox eating a cable.

The total number of protons delivered on target was 9.48 × 1018. This number is not very relevant in terms of the performance of the machine in the sense that the intensity was limited by physics demands.

Lead-ion Run

The lead-ion period started with a five-day run at an energy of 200 GeV proton-equivalent at the request of the NA49 experiment. Thanks to a quick and trouble-free start-up, these five days were squeezed in before the official physics starting date on 25 September, when the SPS was switched to a 400 GeV proton-equivalent cycle. The maximum accelerated intensity in 2000 was 8.8 × 1010 charges/cycle, close to last year’s record of 9 × 1010 charges/cycle. The total number of charges recorded on target was 7.6 × 1015. The major stops during the lead run were due to:

– an 18 kV cable earth fault (twice),

– capacitors blown in a main compensator,

– renewal of the Linac source.

The overall efficiency for lead-ion physics was 89.9%, a new SPS record. In contrast to last year’s run, the lead-ion run did not suffer from any critical days.

SPS Machine Development

Machine Development (MD) studies in 2000 were mainly performed in parallel with physics on a plateau at the end of the operation supercycle. The plateau length could be extended to a significant fraction of the supercycle during the first three weeks of operation when LEP was the only SPS ‘user’. Dedicated sessions (Wednesday MD and Long MD) were devoted to those studies requiring conditions incompatible with physics. The distribution of MD time (scheduled and performed) by type of session in 2000 and the corresponding values for 1999 are presented in Table 1. The quoted numbers include setting-up time. Parallel MD sessions were extended outside of working hours whenever the requests of beam for physics in the CPS was lower. This accounts for the excess amount of parallel MD time. Leptons were made available for LEP even during long machine development sessions, whenever this was compatible with the studies being conducted. The studies performed in 2000 can be subdivided into four main categories:

a) Improvement of the performance of the SPS as a fixed-target accelerator. The optics of the extraction lines towards the North and West experimental areas was verified to provide the input for improvement during the shutdown. Furthermore, the bottlenecks in the physical aperture of the machine were localized and are being checked.

252 SPS + LEP Division b) Preparation of the SPS as LHC injector. The transverse instabilities driven by the beam-induced electron cloud were studied, and both coupled-bunch and single-bunch components were identified. A reduction of the dynamic pressure increase with the integrated current of the LHC beam was measured, but no significant reduction of the electron cloud density was observed. New and upgraded RF equipment (TWC feedback and feed-forward, transverse damper, etc.) was tested during the year, and studies were carried out on the longitudinal instabilities expected for the LHC beam. Measurements of the longitudinal and transverse impedances and of their distribution along the machine were conducted in order to monitor the impact of the hardware modifications performed during the 1999/2000 shutdown. Additional measurements of the optics of the PS–SPS proton transfer line and the extensive use of the OTR profile monitors in TT10 have led to improved dispersion matching at injection in the SPS for the LHC beam transfer. Some transverse coupling has also been identified, whose origins are believed to be in the PS ring.

c) Test of beam instrumentation for the LHC and for the SPS as LHC injector. The Head–Tail monitor, continuous beam profile monitors, bunch-by-bunch intensity and position measurement, and fast scrapers for intensity and tail control were thoroughly tested in the SPS ring and used during machine studies. In addition, the analysis tools foreseen for the determination of non-linear terms of the LHC optics were again tested in the SPS, and provided input for the SPS optics model.

d) SPS as a multicycling machine. The dependence of the beam parameters at injection (tune, radial position, chromaticity) on the SPS magnetic cycle was measured.

Table 1: Distribution of the machine development time in 2000 and 1999

Scheduled 2000 Performed 2000 Scheduled 1999 Performed 1999 Type of session (hours) (hours) (hours) (hours)

Long MD 144 144 156 148

Wednesday MD 56 56 64 73

Parallel MD 720 820 560 700

Total 920 1020 780 921

LEP Operations

The LEP ring was closed on 16 March 2000. Security tests and equipment checks were carried out during the following days and first beam was injected on 29 March, five days ahead of schedule. First collisions at 45.6 GeV per beam were achieved on 3 April. The following week was devoted to Z0 production for experimental calibration, interleaved with the commissioning of high-energy operation. The requisite amount of calibration data had been delivered by 11 April, following which attention turned to running at high energy.

The sole aim for the year was to deliver significant luminosity at the highest possible energies. The maximum operational energy depended on a number of different parameters:

SPS + LEP Division 253 a) Available accelerating RF voltage. Its evolution over the years is shown in Fig. 9. It was increased firstly by installing additional RF cavities, and secondly by raising the accelerating gradient of the superconducting RF cavities from the design gradient of 6 MV/m to 7.4 MV/m.

4000 Beam Available RF energ 3500 voltage [GeV]

3000 115

2500 Nominal RF 105 voltage 2000 Beam 95 energy 1500

RF voltage [MV] 85 1000 Cryogenics upgrade 75 500

Jul-95Feb-96Aug-96 Mar-97 Sep-97 Apr-98Nov-98 May-99 Dec-99 Jun-00 Date

Fig. 9: Evolution of beam energy, nominal RF voltage and available RF voltage.

A given RF voltage determines the beam energy that can be reached, and the likelihood of keeping the beams at this energy is then at the mercy of the stability of the RF system. With such a huge system, running well above design, trips of one or more units are inevitable. With a total current of over 4 mA in the machine, trips were in fact frequent, with the mean time between trips being around 20 minutes. In order to produce a significant integrated luminosity, it was therefore necessary to run with some safety margin. Furthermore, the total current in the machine was limited to around 5 mA in the interests of RF stability. The strategy adopted for most of the year was to go into physics with a safety margin of 2 klystron units. After about an hour, the beam energy was increased during physics to an energy corresponding to a safety margin of 1 klystron unit. After a further hour the energy was again increased until no safety margin was left. Beams were then lost at the first RF trip.

σ b) Maximum horizontal beam size. The horizontal beam size x is proportional to beam energy E, the rms rms β horizontal dispersion D x , the betatron function x and the horizontal damping partition number Jx: β σ α x ⋅⋅rms x ----- D x E Jx

The increase of horizontal beam size with energy results in lower luminosity and larger background in

the experiments. This is counteracted with a high Qx optics and an operational increase of Jx through an increase of the RF frequency. However, the increased Jx reduces both beam energy (longer orbit) and RF voltage overhead (larger energy spread). For maximum beam energy it is desirable to run with the σ largest x (lowest Jx) possible.

254 SPS + LEP Division c) Average bending radius. The energy loss per turn is a function of beam energy E and average bending radius ρ. The average bending radius was changed operationally by using additional bending contributions from horizontal dipole correctors.

The LEP energy was maximized in 2000 by optimizing all of the above contributions. This resulted in physics being carried out at many different energies during the year. The sources of energy gain from 1999 (101 GeV) to 2000 (104.5 GeV) are outlined in Table 2.

Table 2: Contributions to the energy increase in 2000

Energy gain Contribution (GeV)

Additional RF cavities 0.14

Higher RF gradient 0.96

Less RF margin 1.60

Reduced RF frequency 0.70

Increased bending radius 0.17

Total 3.53

Operating the machine under these conditions implied shorter and more frequent fills. While some 2600 physics fills had been made in the whole of the previous 11 years, 1400 more were made in 2000 alone. With refilling so frequent, further efforts to reduce the turnaround time contributed significantly to the integrated luminosity. The average time between physics fills, which was always well over two hours until 1997, was for the first time under one hour in 2000. The machine performance at different energies throughout the year is summarized in Table 3 and Fig. 10.

Table 3: Delivered luminosity at high energy in 2000 averaged over the four experiments

Beam energy Delivered (GeV) luminosity (pb–1)

100–101 0.819

101–101.5 0.651

101.5–102 1.745

102–102.5 7.884

102.5–103 70.169

103–103.5 131.725

103.5–104 4.906

104–104.5 10.734

104.5–105 0.007

SPS + LEP Division 255 ) Luminosity production in 2000 –1 140 <102.5 GeV 120 102.5–102.99 GeV 103–103.49 GeV 100 103.50–103.99 GeV 104–104.49 GeV 80 104.50–104.99 GeV

20 Integrated luminosity (pb

3-Oct 2-May9-May 6-June 4-July 1-Aug8-Aug 5-Sep 10-Oct17-Oct24-Oct31-Oct 11-Apr18-Apr25-Apr 16-May23-May30-May 13-June20-June27-June 11-July18-July25-July 15-Aug22-Aug29-Aug 12-Sep19-Sep26-Sep Date

Fig. 10: Integrated luminosity versus the number of scheduled days of LEP for different energy ranges. In total, a luminosity of 233 pb–1 was delivered to the experiments in 2000.

From Fig. 10, one sees that for the first half of the year the majority of the delivered luminosity was in the energy ranges from 102.5 GeV to 103 GeV (2 klystron margin) and from 103 GeV to 103.5 GeV (1 klystron margin). For the second half of the year, with a more stable RF system, much more running was done with a 1 klystron margin, resulting in nearly all the luminosity being delivered at an energy above 103 GeV in order to maximize the search for the Higgs boson. Also visible in Fig. 10 is a short period in late July where LEP was operated with no safety margin at all, to deliver luminosity at the highest possible energy (above 104 GeV) for a chargino search.

The 5107 hours scheduled for physics were spent as follows:

– Experimental access 5.6%

–Downtime 7.5%

– Filling without coast 15.9%

– Filling with coast 25.9%

– Physics 41.6%

– Energy calibration 3.6%.

As in 1999, the flexible scheduling of machine studies and energy calibration in periods when high-energy running was not possible helped to minimize the impact of various problems on the overall physics production. Nevertheless, the machine downtime of 7.5%, one of the lowest ever for LEP, was a remarkable achievement considering the mode of operation.

256 SPS + LEP Division Power Systems

LEP Operation

During the last year of operation, LEP was pushed to the highest possible beam energy. This meant that many of the power converters were used at, or even above, the rated maximum power. The failure rate naturally increased, but was nevertheless maintained at an excellent level. The mean time between failures (MTBF) was around 18 000 hours, with a relative downtime of 0.6%. The conclusion after so many years of operation is that very high targets of reliability were reached, allowing the converters to be retired with honour.

SPS Operation

The SPS converters showed a slightly worse reliability compared to the previous year, but the variation was well within statistical fluctuations. The relative downtime was maintained at a respectable 0.8%. The recent COD converters confirmed their very high reliability, with the exception of one incident where an extreme mains perturbation killed more than 30 CODs in two auxiliary buildings. Investigations are under way to ensure that this is not repeated in the future.

Experimental Area Operation

The converters in the experimental areas continued to perform at a reliability level of 15 000 hours MTBF. Discussions to consider changes to the software structures have started, which will enable a future renovation programme to be undertaken with minimal disturbance to operation. At this time, no resources are available to study the necessary hardware changes or to start any development.

SPS Renovation Project

The renovation project for the auxiliary SPS converters entered the second production phase. All the new converters and most of the renovated ones have been delivered to CERN and have been tested successfully. The new regulation electronics was produced by industry and will be integrated into the system at CERN.

LHC Project - Main Ring

High-Current Converters

The 13 kA, 16 V converters produced by one of the contractors have been factory tested, and are being delivered to CERN for installation in the SM18 String2 test zone. The other contractor failed to produce a functioning prototype and the contract was cancelled. The market survey for the main series production of the 3.25 kA and 2 kA modules has been prepared for a tender inquiry in 2001.

SPS + LEP Division 257 One 14 kA, ± 16 V converter has been installed for the magnet test benches and used to test the first of the main quadrupole prototypes. Two more units have now been delivered to CERN and are awaiting installation. A further two units are on order to complete the needs for the magnet test benches.

The 24 kA, 6 V converter for testing the ATLAS superconducting coils was also successfully commissioned.

Low-Current Converters

The 24 four-quadrant, 600 A, 10 V converters have been successfully deployed in the magnet test benches, String2, and other test installations. The market survey for the main series production has been completed and a technical specification is in preparation.

Two prototype four-quadrant, 60 A, 8 V converters are working and are being used to verify the performance and radiation hardness of the chosen components. Construction of 14 more units was started in November. The power part has been radiation tested with success to 20 Gy, but the experience has demonstrated the necessity of further testing for certain critical components.

A control interface definition has been produced and is being tested for all converter types, while a power test area has been set up for the reception testing of all power converters at CERN before their installation.

Converter Control

A second hardware prototype of the complete digital controller system was built and fully evaluated. The associated software was also completed and the entire system was successfully tested in a number of power converters. The construction of a small series for use in String2 and the magnet test benches was completed. Commissioning started at the end of the year. The hardware will be progressively installed in 2001 for both applications.

External consultants completed the testing of the high-precision Sigma-Delta ADC. The results confirmed and extended the measurements made at CERN, fully validating the performance requirements for the LHC. The development and extensive performance evaluation of a lower precision, dual ADC card has also been completed.

Radiation tests of electronic components continued throughout the year. An automatic error detection and correction circuit was tested with good results, and looks a promising solution to the problems encountered with memory circuits. Extensive testing could not be pursued because of the short radiation test periods this year. Radiation tests were also performed on a number of industrial power supply modules to verify their suitability for many LHC applications. The tests have been very fruitful and will continue.

Development of the WorldFIP gateway has progressed with the inclusion of GPS timing to microsecond precision. The software for the gateway and digital controller now permits extended testing. A Web-based documentation system is being developed to ensure a close collaboration with the outside developers of the application software.

258 SPS + LEP Division High Precision and Calibration

Testing of the second prototype current calibrator was completed, and an improved design for the transducer head assembly was proposed by CERN and obtained from industry. This new component has been incorporated in an improved, fully computer-controlled electronics system. The very good results have been cross-checked with the NPL in the UK and show that the calibration system should meet its target of 1 ppm accuracy.

The first contracts were awarded for high-current DCCT prototypes with calibration windings. The prototype from one contractor has been approved and a small series was delivered at the end of the year. A second contractor is currently working on improvements.

LHC Project

A review has been performed to study the possibility of pulsing a larger number of the beam transfer converters. This would enable some cost savings and minimize installation work. Preparations have started to modify the building infrastructure where the converters will be located. A pre-series COD converter has been made and is being tested operationally in the SPS. A Market Survey is in preparation for the modification of the LEP converters that are to be re-used.

The design of components for fast current measurements in the MUGEF system to provide an SPS extraction interlock has been completed. System performance evaluation is under way to confirm the required speed and reliability. Construction of the MUGEF control hardware is also well under way.

Standards Laboratory

Primary Standards

The primary standards programme is now running very smoothly and includes the 10 mA current standard developed for CERN. Operational improvements have been proposed to further establish the noise performance and increase the calibration accuracy. A contract has been placed for the manufacture of the more than thirty 10 mA current standards necessary for the LHC project. Their timely delivery will ensure that sufficient calibration history exists before large-scale deployment.

20 kA Testbed

The 20 kA testbed has proven its worth in evaluating DCCTs delivered from industry, both for the SPS renovation project and the prototypes for the LHC. So much experience was obtained from these campaigns, that it was decided to build additional, smaller testbeds for lower rating DCCTs.

SPS + LEP Division 259 New SPS DCCTs

The DCCTs delivered from industry for the SPS renovation project were full of surprises and were outside the specification on many points. It must, however, be recognized that it is difficult to satisfy the special and very demanding requirements of CERN. A programme for improvement is under way, but some types had to be abandoned altogether. A new contract was placed with another manufacturer with more experience and more reliable products.

Evaluation of LHC Prototype DCCTs

The first pre-series 13 kA DCCTs with calibration windings were evaluated and approved. The concept and accuracy of this method has involved extensive and delicate measurements. Although many difficulties were encountered in these system tests, most of them have been overcome and the product has been qualified to a better than 2 ppm accuracy.

260 SPS + LEP Division Technical Support Division

Introduction

The mandate of the ST Division is to provide technical support for existing accelerators and related experimental areas, for the LHC and other projects, in the fields of civil engineering, cooling with air and demineralized water, electrical installations, heavy handling, access control, gas and fire detection, and monitoring of the technical infrastructure. In addition, ST Division is responsible for the management of facilities related to buildings, such as heating, air-conditioning, low-voltage electrical systems, cleaning and landscape maintenance.

The mandate covers investment made over 45 years, amounting in value to some 3500 MCHF which needs maintenance and consolidation; such investment is the basis for CERN’s ongoing developments in accelerators and experimental areas.

Proper operation and maintenance of these facilities and adaptation to changing requirements implies the need for sound resources management in terms of staff and budget allocations.

The maintenance work, together with part of the operation duties, is carried out by industrial support contractors and, though some of the contracts have been recently retendered, a significant number of tasks, will soon be regrouped in a smaller number of larger contracts.

The expected reduction in staff numbers over the next years is a major managerial challenge, giving the opportunity to adapt the staff’s technical profile, to continue and rationalize the outsourcing programme, and consolidate the project-oriented ST structure.

The following table summarizes the general parameters and the investment cost of equipment under the responsibility of ST Division.

Technical Support Division 261 General parameters and investment cost

Investment General Parameters MCHF

Surface buildings 570 1300 Tunnels 54 km 1200 Roads 23 km 50

Vehicles 2500 100 Lifts 310

Access control 65

Fluids distribution piping 300 km 550 Heating plants 70 MW Cooling and ventilation equipment

Main substations and reactive power compensation 84 High-voltage network 120 Low-voltage distribution 75 Control 6

Activities

The ST Division’s activities are in three domains:

Support for Existing Accelerators and Areas

The following systems are operated and maintained: cooling, air-conditioning and ventilation systems, electrical supply and distribution, heavy handling cranes and lifts, access control of LEP, SPS and CPS machines and related experimental areas. In the operation field, the Technical Control Room (TCR) plays an important co-ordination role.

The detailed study for a simplified and modernized cooling and drinking water distribution system over CERN Sites was concluded and the related work started in 1999.

The Cooling Group is also involved together with the ‘Services Industriels de Genève’ (SIG) in the overhaul and modernization of the water treatment plant at Vengeron on the lakeside. This will lead to a complete renewal of the primary cooling systems for machines. This in turn has motivated a critical examination of CERN’s water consumption which has led to the technical proposal to close all water cooling circuits in loops equipped with cooling towers. This project will led to two essential improvements following substantial technical and financial investment.

262 Technical Support Division First, the total CERN water consumption will be halved and second, the ‘Peney’ water sources can be ‘moth-balled’ as a tacit reserve and thus a considerable renovation programme of these installations can be avoided.

These studies have been completed and a contract between CERN and SIG has been signed following the authorization of the Finance Committee.

LHC Machine and Experimental Areas

A significant budget will be committed to the LHC project, mainly in civil engineering, cooling and ventilation, and electrical equipment in the next three years, with a high peak of work in 1999/2003 for the three ‘lots’ of civil engineering work. All the work must be carried out, in accordance with the LHC machine and caverns construction schedule, by the end of 2003.

In 2000 the work for the LHC Project comprised the principal task of the Civil Engineering Group and a major one for the Cooling and Ventilation Group which are in charge of accommodating the requirements of the LHC experimental programme of ATLAS and CMS in two underground caverns and the numerous and complex buildings at the surface necessary for both the experiments and the accelerator. There was a great deal of interaction between the Civil Engineering Group, the Cooling and Ventilation (CV), Electrical Engineering (EL), and Alarms and Acces (AA) groups, the accelerator specialists and the experimentalists to determine the optimum layout of caverns, tunnels and surface buildings within the constraints of stringent budget limitations.

A major contribution to LHC is ST participation in the French Installations Nucléaires de Base (INB) preparatory work.

General Services to the CERN Community

The Technical Facilities Management Group (TFM) is the centre of all the general services to divisions. It calls upon the services, provided through its contracts, for the execution of the work and will avail itself of the advice and guidance of other specialized ST groups.

Reorganization Actions

To ensure a coherent and homogeneous technical approach to the work, the following initiatives have been studied and implemented:

– A study aimed at rationalization and regrouping of the facilities management contracts, and at opening the possibility of competing to various Member States, was carried out and the Market Survey was sent out in early 2000.

– The contracts will be more attractive as the annual turnover for each contract will be higher.

– The technical profile of ST staff has been increased by appropriate recruitment.

Technical Support Division 263 – Initiatives have been taken to improve the ST Division’s external and internal communication and collaboration and to increase staff motivation:

– An annual ST Workshop has been organized in February since 1998 and one is scheduled in 2002.

– The principal partners of ST Division are invited to participate in order to start, improve, or establish the necessary technical and human dialogues at various levels.

– The expected return in terms of communication, motivation, elimination of taboos is significant for a reasonable cost.

– The work of two technical committees created in 1997, one dedicated to machine operation and maintenance and the LHC project, the ST Technical Committee, the second to general services problems, the General Services Technical Committee, has been very satisfactory.

Management and Organization

DI group action has been to support:

– the division leader and the group leaders in questions concerning contracts, budgets and personnel matters;

– the Division in planning matters: financial, technical and manpower;

– supervisors, contract managers and budget holders;

– ST staff in practical personnel matters;

– groups in application of INB and other safety legislation;

– creation and/or updating of ST quality procedures.

Alarms and Access

General

The present mandate of the group comprises:

– Definition, procurement, installation, testing and maintenance of fire and gas leak detection and of evacuation systems for all CERN premises, accelerators and experiments.

– Transmission of safety alarms (level 3 alarms) to the Fire Brigade.

– Definition, procurement, installation, testing and maintenance of controlled access systems for the site and building surveillance (SUSI) as well as for CERN’s radiation areas (ZORA).

– Documentation and implementation of recommendations of the French authorities concerning the Installations Nucléaires de Base (INB).

264 Technical Support Division – Intensive collaboration with CERN safety officers (TIS, GLIMOS, DSO, TSO, etc.) and with the Fire Brigade.

These activities are carried out by two sections:

– Safety Alarms Section (AS) - Fire/gas detection, oxygen deficiency detection, safety alarms transmission.

– Access Control Section (AC) - Safety systems for accelerators and experimental areas (access control and beam interlock). Site access control.

Safety Alarms

The scheduled long-term equipment renewal programme was continued. During the year several fire detection installations were replaced on the Meyrin site. Renewal of safety systems in Meyrin and Prévessin was started and will be completed early next year.

Interventions by the Fire Brigade on alarm systems due to spurious alarms were significantly reduced.

Requirements for fire detection for the LHC surface buildings were determined, culminating in a co- authored document from TIS and ST/AA/AS. Requirements for alarm systems for the LHC machine and experiments are being analysed in several working groups.

An Invitation To Tender (IT-2696/ST) for the supply of gas detection systems for the LHC and renewal of existing installations was sent out. The contract was approved by the Finance Committee of September 2000.

A Market Survey and an Invitation To Tender (IT-2818/ST) for the maintenance of all safety systems, concerning fire and gas detection were sent out. This contract will replace the current maintenance contract which expires next year.

A Market Survey (MS-2891/ST) was sent out in order to select firms capable of supplying the alarm systems for the LHC experiments.

Access Control

Site and Building Access Control and Surveillance

During the year, the surveillance of the site was extended through a new contract to the sites of the LEP/ LHC with the services of guards and especially the assistance with the LEP dismantling (traceability). The activities of locksmithing and parking surveillance were integrated in the base contract, which already comprises reception, records and surveillance.

The renovation of the LEP/LHC access control systems which started three years ago was continued.

Technical Support Division 265 The new contract for the supply and maintenance of the access control systems was prepared and put in operation at the beginning of 2001.

A new access system on the top of the LEP shafts was installed in order to satisfy the requirements of safety and traceability imposed by the LEP dismantling. This system will be re-used for the access control to the SD and SX buildings of the LHC.

Safety Systems for Accelerators and Experimental Areas

In addition to the consolidation and maintenance of the safety systems, a number of new projects and works were conducted in the PS complex such as the primary and experimental areas of the AD, TOF and CTF3. Also, the removal of the control racks from the MCR was started.

SPS

The functions and the technology of the safety systems at the SPS access points were renewed to satisfy the needs of the upgrade of the database (on-line) and especially suppression of the access mode ‘free’ during the SPS shutdown. The first approach for the modification and adaptation of the SPS safety systems for the CNGS and LHC injection was made.

LEP

The dismantling of the LEP safety systems was prepared and started together with the reports concerning the INB.

LHC

A preliminary study concerning the identification of needs (testing zones, access modes and procedures), performance, and constraints for the LHC safety systems was launched in view of the preparation of the technical specification.

Civil Engineering

The LHC Project

Package 1

By the end of 2000 almost all the surface works were completed. The only outstanding buildings are those that cannot be completed until the underground works are finished. In addition to the surface works included

266 Technical Support Division under the main contract, the Package 1 contractor was also awarded a further contract for the construction of cooling towers and pump stations at Point 1. These were also completed at the end of 2000.

For the underground works, the contractor is expected to finish all the work associated with the USA15 cavern on time. This cavern has been fully excavated and over 75% of the final lining has been installed. Completion is expected more or less on time in the middle of 2001. For the UXA15 cavern the contractor is slightly behind schedule owing partly to lack of progress by the contractor and to a cumulation of minor delays outside the control of the contractor. The delicate operation of excavation of the vault was completed succesfully and it is expected that the permanent lining will be completed in the middle of 2001 after which excavation will continue down to the cavern floor level.

Package 2

Surface works on this package have proceeded well with a large proportion of the surface works handed over to CERN in 2000. Work will continue on the SUX5 and SGX5 buildings in 2001 with handover of both buildings expected in the middle of the year.

The problems encountered in 1999 during the ground freezing operation were succesfully overcome in early 2000 and both the PM54 and PX56 shafts were excavated and lined. Work on the concrete pillar between the two caverns commenced and will continue in 2001. It is expected that excavation work on both large caverns will commence towards the middle of 2001.

Package 3a

The TI2 tunnel excavation was 80% completed in 2000 with the remaining work to be done in early 2001. Some problems with water intrusion and floor movement were encountered but these were dealt with without major difficulty.

Surface works at Point 18 were completed as well as the SHM4 and SDH4 buildings at Point 4. The SHM8 building at Point 8 was 90% complete by the end of the year.

Package 3b

Despite many problems encountered by the contractor, the excavation of all the TI8 tunnel was completed up to the LEP radiation limit. Four hundred metres of the tunnel lining were also installed. The connection to the SPS was totally excavated and the connection borehole for the beam pipe was made.

Technical Support Division 267 Other Projects

CERN Neutrino Beam to Gran Sasso (CNGS)

The contract for the construction works and the supervision of the works was approved by the Finance Committee in June 2000. Work commenced in September and by the end of the year about 15 metres of the access shaft had been exacavated and a large proportion of the contractor’s facilities installed on the surface.

CLIC

The ST-CE group played an important role in the development of the CLIC project during 2000. Geological studies where made and possible locations for the project were investigated.

Other

Other important contributions were made by the ST-CE group to the following projects:

– SPL project - layouts and cost estimates prepared;

– TOF project - works almost complete;

– CTF3 project - design work carried out and preparation for second phase;

– CEMB project - design work carried out and brochure presented.

Smaller projects completed by the group include the construction of the SUI8 building, civil engineering works for the water project, the construction of the LEP dismantling area at Prévessin, and many other minor structures located around the various CERN sites.

Personnel

The Group comprised 23 members of staff for the first half of 2000, increasing to 24 with the arrival of a technician in July 2000.

Cooling and Ventilation

General

Previous structural changes in the Cooling and Ventilation group, reported in the 1999 Annual Report, were fully implemented, with good results. The work load for all members in the group has continually increased, with many new projects that have turned into the construction phase. Personnel changes are frequently made between the sections so that the qualifications are used in an optimal way. The main

268 Technical Support Division alterations are due to the sharp increase of construction work sites for the LHC, the Water 2000 project, and the definitive decommissioning of the LEP accelerator with its subsequent dismantling.

Design

The design office was used to its full capacity for the production of engineering studies and drawings during the year 2000. This is mainly due to the LHC project, but other projects, such as the Water 2000 project, have contributed to keep the activity on the limit of its resources.

Ventilation and Air-Conditioning

The most important technical study was for the ventilation and air-conditioning of the two new main caverns in the LHC project, namely for the ATLAS and CMS experiments. This very complex system was designed in the group, and a call for tender was successfully finalized before the end of the year. This particular project was extremely demanding; more than 2000 drawings were made for this project, of which 200 are stored on the CERN Drawing Directory (CDD).

The detailed pre-engineering studies for the LHC tunnel and the new transfer tunnel’s air-conditioning were also launched during this year.

Smaller projects within the frame of the LHC project whose design phases were accomplished in 2000 include the air-conditioning of the assembly hall for the ATLAS LAr and Inner Detector, and the CMS ECAL H4. Finally, the design section successfully accomplished the engineering of the air-conditioning of the SPS tunnel as well as the TT2 tunnel in the PS Complex.

Fluids

The tendering process for the supply of chilled and mixed water plants for the experimental sites of ATLAS and CMS was finalized and the contract awarded. The tendering process of some other fluid-related projects like the pipes in shafts and galleries was completed.

An important design study was that of the stainless steel pipes to be installed in the main ring of the LHC. In order to optimize resources and rationalize the installation, ST/CV and LHC/ACR (Cryogenics for Accelerators) are collaborating for common piping contracts like the one for a total of approximately 200 km of stainless steel pipes to be installed in the LHC tunnel. This will go out as a call for tender during the first half of 2001.

Several projects which focused on the consolidation of the PS Complex cooling plants were also completed in their design phase, like the refurbishing of the cooling plants for the South and East Experimental halls as well as the chilled water piping in the PS tunnel.

The design team has also been continuously involved in the Water 2000 project, see below.

Technical Support Division 269 Thermal Analysis and Cooling Systems for Detectors

The support activity for the detectors continued to increase in 2000. Some additional resources, mainly students, a ‘coopérant’, and a project associate, have made this possible, in addition to the help provided by our visiting engineer from the German firm ILK. The most recent activities in this area cover studies for ALICE, ATLAS, and CMS for which some examples are mentioned below.

– The thermal influence of the Transition Radiation Detector (TRD) on the drift gas of the Time Projection Chamber (TPC) in ALICE was studied as well as the cooling of the Muon Tracking Chambers enclosed in the ALICE dipole volume. The High-Momentum PID was also the object of a calculation aimed at the improvement of the cooling concept.

– A preliminary study for the cooling of the dump resistors for the ATLAS magnet recently began in collaboration with EP Division. Also, the muon chambers’ environment analysis is under way to study local velocities and the temperature differences between the chambers’ external sides.

– For CMS, the CV group made improvements in the design of the power and regulation cooling circuits of ECAL. In this field the team also made proposals for the control of temperature in the circuits, and is now tackling the ECAL prototype called Module 0, for which CV group is helping with the design and implementation of the external piping together with the pressure and temperature sensors and the data acquisition. The CMS muon chambers were the object of hydraulic calculations of the head losses in the fluid circuits, as was also the case for the CMS preshower where the thermal screen was analysed along with the thermal bridges provoked by the feedthrough connectors.

In addition to the support given to the experiments, some other calculations are in progress for the ventilation of the LHC tunnel accounting for the thermal loads and geometry of the LHC accelerator equipment and for the cooling transition of the LHC thermal shield in the cryostat.

Control and Process Automation

The control and electricity team in the design unit worked not only on the control concepts for all new projects like the heating and ventilation of the LHC surface buildings, and the primary cooling stations for the experiments mentioned above, but also in the implementation of these projects during the works phase. In addition to this, consolidation projects in the control of existing cooling and ventilation facilities continued with the major engineering of the SPS cooling plants. The tendering process of a contract for the Software Support for Industrial Controls, ‘IT-2711/ST’, was completed and now enters the work phase. The LEP Control Migration project was integrated into existing modification projects for the LHC, such as those for the underground cooling plants and the tunnel air conditioning, and good progress was made for the engineering work. The maintenance of some specialized instrumentation in the existing machines was also followed by the team.

Works

The Works section saw activity increase throughout the year as the installation phase for a lot of the LHC related contract began and LEP was finally closed down. From November, all the major works related to the

270 Technical Support Division annual shutdown of the SPS have started, namely the Water 2000 project and several others for the LHC fluid installation.

Heating and Ventilation of LHC Surface Buildings (Contract F-300)

The construction phase, which started in September 1999, has moved on in several surface points along with the completion of the civil engineering structures. Point 18 was completed (buildings SD, SHM and SMA), while work is in progress on Points 4 (SDH and SHM) and 5 (SH and SX). The schedule is being respected and no particular problem has been encountered. The work is planned to continue in the coming years, until 2003.

LHC Cooling Construction

The installation phase started during year 2000 with the internal components of the cooling towers and the associated pumping stations at Point 1 and Point 5. The civil engineering structures were delivered for these items during the autumn and the mechanical erection is now progressing according to plan. The first cooling towers (Point 1) will be ready in May 2001, as they are shared between the LHC and SPS.

Another fluid project for the LHC that was finalized during 2000 is all buried pipelines, installed at Point 1 and Point 4.

The Water 2000 Project

All the contracts related to the restructuring of the CERN water supplies, the Water 2000 Project, were signed during the summer and the installation phase was started in November, as the LEP and the SPS accelerators have been stopped. Almost all the work is foreseen to be completed by May 2001; the main activities are as follows:

– replacement of the air handling units for the SPS tunnel in BA2, BA4 and BA6,

– installation of chilled water production plants in all the BAs,

– dismantling and renovation of the SPS primary cooling circuits,

– replacement of the plate heat exchangers in all the BAs,

– upgrade of the West area, Prévessin and SPS cooling towers,

– installation of air handling units for the conditioning of the control rooms in all BAs.

The Works section was also involved in the construction work of the part of the project that is under SIG supervision; in particular the following activities were developed:

– completion of the building of a new pumping station, the WS NET, and its commissioning in September 2000,

– installation of a pipelines from the WS NET pumping station to the Meyrin and Prevéssin sites,

Technical Support Division 271 – completion of the construction of a new valve chamber close to the C Entrance of CERN (in May 2000),

– dismantling and renovation of the SPS and LEP pumping stations (to be finished in July 2001 for the SPS and in December 2001 for the LEP/LHC),

– pipe connection to the SPS cooling loop and installation of a valve chamber in case of problems on the SPS cooling towers.

The planning has been respected and no major problem has occurred so far.

Operation

The definition and implementation of an effective set of performance indicators in the context of the maintenance contract was one of the most important items of progress during the last two years. It represents a clear image where important concepts like equipment availability or operational flexibility have been translated into measurable and usable parameters. These are the indicators that actually provide the section with the data required for all performance statistics. Because of the dimensions of the equipment park, spread over more than 550 hectares, a correct follow-up of the maintenance activity requires an effective ‘Computer- Aided Maintenance Management’ system (CAMM) and in 2001 the new CAMM system will be fully operational.

PS Complex

The operation activities directly related to the cooling and ventilation of the PS complex show good results this year, with a very low rate of down-time due to problems with the cooling of the machines, up to 50% reduction when compared with 1999.

The PS Complex is characterized by the longest run period among all the accelerators at CERN. During the normal shutdown period there are several experimental areas that require constant water-cooling for their appliances. For this reason, the time allocated for maintenance work in PS cooling stations is limited to very short periods. It is worth mentioning that the PS cooling installations are the oldest at CERN and therefore their maintenance requires more time and resources. Besides the normal maintenance and operation work, the PS team was heavily involved in the modification and improvement works of its equipment in 2000. They include the commissioning of the new Booster cooling station, replacement of the chilled water pipes in the PS tunnel, and the replacement of the air handling units in the TT2 tunnel. A few new installations were constructed, i.e. the TOF cooling station and a demineralized water cooling station in Bldg. 180. The workload will certainly increase during the next few years when the PS Complex together with SPS installations will be the only ones running at CERN until 2006, when the LHC is finished.

272 Technical Support Division SPS

In year 2000 the operation of the CV equipment of the SPS accelerator was stable and the equipment performed well in general. Only 1.6 hours downtime was attributed to the SPS cooling team. This is the best result in the last six years in terms of availability of the cooling and ventilation equipment.

The installation of the new chilled water station in BA3 was the major modification carried out during the 1999/2000 shutdown. This was a crucial task since this included changing the cooling system of the LEP/SPS control room and the Faraday cage in BA3. The chiller has performed well, apart from some minor running-in problems.

The operation team of SPS was heavily involved in the update of the SPS for the LHC and the Water 2000 Project, see above. The closing of the raw water supply line for the SPS and the related replacement of the SPS demineralized heat exchangers along with the upgrade of the SPS cooling towers gave the team a heavy workload.

LEP

At the last run for LEP, despite a very high demand for physics and the continued increase of the beam energy which has pushed all systems to the limits, the operation of the cooling and ventilation equipment was very stable and the installations have provided the usual high level of availability and reliability. 10.4 hours of downtime were attributed to LEP operation, three major failures and 2.7% of the total downtime for the LEP physics. The most serious breakdown took place in the last week of the prolongation period of LEP. It is worth noting that the number of hours of downtime due to ST/CV equipment in 2000 decreased compared to the preceding year in spite of the increased demand for cooling capacity.

Utilities

The activity carried out by the utilities team, heating plant, pumping stations and co-generation plant, had a favourable year with good results with regards to availability and operational flexibility. It is worth noting that there were no major breakdowns of the pumping stations or of the heating plants. The Co-generation Plant was entirely available during its stand-by period, however, its use has changed drastically with the new tariffs of natural gas and electricity that apply to CERN.

An improvement in the running of the heating systems has been clearly noticed since the implementation of a stronger energy-saving incentive in the maintenance contract.

The most important change in the operation of the pumping stations is, again, the Water 2000 Project.

Technical Support Division 273 Electrical Engineering

The LHC Project

The activities of ST-EL group during the year 2000 were increasingly concentrated around the LHC project. A major activity was the upgrade of the 18 kV substation SE 18 in the LHC 18 zone. From being a fairly small installation serving originally only the SM 18 building, it is now a power distribution point for the whole zone, developed along the lines of the LEP substations. It has two 18 kV switchboards: one for general services and one for the test systems and cryogenics. The substation has a complete set of auxiliaries, and is fully inserted in the power network monitoring.

In LHC Point 1, studies were prepared for the new surface buildings, and the installation requirements underground were advancing. The power installations of the USA 15, with its 18/0.4 kV transformers and main 400/230 V switchboards were determined and located on the installation layout, as were the main cable ways. The delicate job of finding cable routing through the highly sensitive areas of the service cavern, where the experiments electronics racks are installed, has progressed well.

LHC zone 5 saw intensive installation activity as the surface buildings were delivered to the services, in particular buildings SX, SH, SGX and SF.

The extension of the 18 kV substation of LHC Point 5, one of the major electrical infrastructure upgrades for the LHC, was studied during 2000, with work due to start during winter 2000/2001. This substation will receive high-voltage switchgear recovered from other LHC points, where the equipment previously supplied LEP machine systems. In order to minimize the overall cost, the substation will be installed in the former SR building, no longer needed for the rectifiers. In a further attempt to make best possible use of the civil engineering, the 3.3 kV substation dedicated to experimental cryogenics will be located in the SR building, together with the 18 kV equipment. The SE building, hitherto housing the substation, will be used as a safe- room. This whole array of installations were studied and prepared in 2000.

The studies of the installations for the injection tunnels, TI2 and TI8, had to follow a number of changes in the policy for the installation of the power converters. The SL-PO group managed to obtain a considerable economy through an altered disposition of the converters, with respect to what was originally used as a working basis. The powering and cabling studies by ST-EL can now proceed on a solid basis, these changes were finally frozen.

An important aspect of the study work for the LHC is the integration of all equipment on three- dimensional layouts. ST-EL has played, and will continue to play, an important role in the field of equipment and rack implementation, within the framework of the LHC working groups under the LHC Technical Co- ordination Committee (TCC).

ST-EL has provided the cabling and the layout studies for the String 2 project, as well as the complete AC powering system.

From July 2000 the Telecom section joined IT Division.

274 Technical Support Division Consolidation Projects

The main project for ST-EL, outside the LHC project, is the renovation of the 400/18 kV BE substation, combined with the installation of a third reactive power compensator.

The work on the BE substation started during the 2000/2001 shutdown. The substation will be entirely renovated, both on the 400 kV level and at the 18 kV level. The substation will in the future be dedicated to the pulsed load only. It is conceived to give a maximum of flexibility of operation, and will allow outage of one of the major elements, whilst allowing the SPS to continue operation.

The contract for the third compensator was signed in summer 2000, and in the meantime preparations by the contractor, ABB, have progressed well. The civil engineering needed for the installation of the compensation equipment is under way.

The uninterruptible power supply systems of the BA buildings of the SPS were exchanged during 2000. The old units, being totally obsolete, were replaced by modern units. The small control rooms in the BAs were equipped with similar, though smaller systems.

During the shutdown an important amount of work was performed for the SPS big bang and the SLI project, mostly in the field of cabling modifications, but several specialized installations, like Faraday cages, had their power distribution renovated.

CNGS

The ST-EL contribution to the CNGS during 2000 was concentrated around installation studies of the tunnel stretches common between the LHC injection tunnel and the CNGS tunnel. Further details concerning the space for installation of equipment in the target area were studied.

Contribution to Water 2000

At the beginning of 2000, ST-EL terminated the renovation of the BB6 18 kV substation, feeding the pumping stations at Meyrin. Several major interventions, implying major 400/230 V installations in the SPS buildings were also performed. The project’s requirements also covered the addition of three 18 kV cubicles, recuperated elsewhere in the SPS, each with an 18/0.4 kV transformer and downstream distribution.

Operation

On the exploitation side, the year was divided into two distinctive phases: before and after 22 September. Before that date the group had had a practically zero-fault record; from that day started a series of cable faults in the ageing SPS 18 kV buried cable network. Because of this an important number of machine hours were lost. The apparent degradation of the buried network led to the definition of a future project for renovation of the SPS.

Technical Support Division 275 Network Monitoring

The central system of the new SCADA system was installed in the building of the Jura substation, control equipment was installed in the SE 18 and the SE 1 substations; the preparations for the substations BE9 and BE, including the third compensator, is well under way. The transfer of the data from the MICENE system to the SCADA system is progressing.

Databases

The database systems of the group were modernized during the year, with the transfer to MP 5. Modules for equipment management within the new service contracts and a new ‘cablotheque’ are under way.

LEP Dismantling

During the first phase of the LEP dismantling, the ST-EL group was involved in decommissioning and making safe the electrical installations, a task that was dealt with to the satisfaction of the project. The ensuing dismantling work was taken care of, and the group has played, and will continue to play, a positive role in this context.

Group Structure

During 2000, a new group structure was prepared, aiming at an even more project-oriented organization. The number of sections was increased and the subsections were abolished, creating a broader and flatter organization that should allow better vertical communication in the group. A refined task distribution for the LHC underground installation work was also prepared.

New Contracts

Several supply contracts were prepared and started during 2000, and the new generation of service contracts were adjudicated. The service contracts prepared during 2000 cover electrical installation work, cabling and exploitation support. The supply contracts for the high voltage were renewed.

Optical Fibre Installation

During the year it was decided to integrate into ST-EL from January 2002 the optical fibre installation activity, hitherto part of SL/CO. The transfer has taken place in the meantime. The team prepared itself for the transfer in a very positive way, which augurs well for the future activity.

276 Technical Support Division Diesel Generator Sets

During the year it was decided to re-integrate the diesel generator sets into the ST-EL group. The maintenance work will in the future be handed over to a contractor, as a natural transition, as the team shrinks from three persons to one person who will have essentially the responsibility of technical contract manager

Heavy Handling and Transport

General

The year 2000 brought some major changes in the group organization, mainly due to the numerous retirements of CERN staff. The increasing workload and diminished resources required a tighter and well- organized group structure. The main reason for restructuring the group into four units was to establish a clear distribution of functions corresponding to the needs of the LHC project. The new headquarters of the Transport and Handling Group is the newly renovated Bldg. 57.

Operation Unit

On 1 July 2000 the new contract S090 for the ‘Industrial Support for Transport and Handling’ was set up. The new contractor, DBS, has to not only provide the workforce to cover the standard CERN workload but will also have to meet the requirements of the new projects, such as the LEP dismantling, CMS assembling, and LHC installation to name only a few.

Apart from the standard workload, such as accelerator shutdowns, the year 2000 showed an increasing demand for transport and handling of equipment. This was mainly due to the start of the LEP dismantling and the entering into the assembly phase of LHC magnets and detectors.

Since 1 May 2000, the maintenance organization and co-ordination of the transport and handling equipment used by the Operation Unit is now assured by themselves. This has the advantage that the Operation Unit, which is directly involved in the project planning, can better assess the required equipment maintenance.

The contract E056 with Delattre-Belleli for the execution of equipment maintenance came to the end of its three-year term in September 2000 and was prolonged for another year without any major changes.

The following list of activities shows only a part of the various tasks of the Operation Unit during last year.

a) Meyrin Site

The activities in year 2000 were mainly to guarantee the transport and handling service for the various accelerators and for all CERN users on the Meyrin site. In particular, the completion of TOF should be mentioned since it was a major challenge to install the new experiment in one of the old ISR annexes.

Technical Support Division 277 b) Prévessin Site

Assuring the proper execution of transport and handling activities during the shutdown of SPS and its annexes.

Organization of the upcoming long SPS shutdown 2000/2001, which is essential for the preparation of the SPS accelerator for the future LHC running.

c) LEP

Assuring the proper execution of transport and handling activities during the very short shutdown in order to allow an extensive physics programme for the last year of the LEP accelerator.

All through the year the installation of new LHC infrastructure went on, as for example the installation of huge helium reservoirs at all LEP/LHC points.

The rest of the year was mainly devoted to the organization of the forthcoming dismantling of the LEP machine and experiments.

d) Maintenance

The major activity besides the standard equipment maintenance was the general overhaul of lifting and transport equipment that is foreseen for an extensive use for the LEP dismantling (monorail system etc.) and for the long SPS shutdown.

Logistic Unit

The Logistic Unit experienced a constant increase of activities mainly because of the preparation for the LEP dismantling and the progress of the LHC project.

– Passenger transport by a regular operating shuttle service from and to the CERN premises and on demand for the Visitor Service, conferences, seminars, workshops etc.

– Organization and co-ordination of the office removal service and merchandise distribution on the CERN premises.

– Procurement, organization and management of CERN’s car fleet that consists of about 610 vehicles for the transport of people and light equipment. The CERN car fleet is renewed and maintained according to a fixed programme that is accepted and monitored by CERN’s Car Pool Committee.

– Procurement, organization and maintenance of the group’s utility vehicle fleet that includes 69 utility vehicles, 50 lorries, tractors and road trailers, 108 electromechanical vehicles and machines, 173 ground maintenance vehicles and machines, and mopeds.

278 Technical Support Division Design Unit

The Design Unit is responsible for the technical specifications and drawings for the procurement of new transport and handling equipment and for major modifications on already existing equipment.

In year 2000 the following new contracts for the procurement of new equipment and for major modifications on already existing equipment were signed:

– The procurement of 110 containers, 44 pallet trucks and other various small equipment for the LEP dismantling.

– Two contracts were signed for the renovation of eight SPS lifts and for 10 lifts in office buildings. Another contract is in preparation for the renewal of five non-conforming lifts.

In addition, a shielded door for the storage building BSPR in Prévessin, several small hoisting gear and other lifting equipment were acquired.

The main focus was the study and design of seven new LHC lifts and seven new LHC overhead travelling cranes including a 280-ton crane for ATLAS. The design phase is almost complete and the contracts will be signed in the first half of 2001.

Works Unit

The section is responsible for the correct installation and commissioning of new equipment and for major modifications on already existing equipment. This work has to be done by respecting the CERN procedures and in close collaboration with the Design Unit that is responsible for the technical specifications and drawings. In the last year, the following equipment was installed or underwent major modifications:

– Contract LHC Lot 1–TAIM: two overhead travelling cranes of 80 tons each were installed and commissioned for CMS in building SX5.

– Contract LHC Lot 2–ITALKRANE: six new overhead travelling cranes were installed and commissioned for the new LHC buildings SH5, SF5, SDH4, SHM4, SUX1 and SF1.

– Twelve new motorized doors were installed and five lifts were put into conformity with the new legal requirements.

Monitoring and Operation

General

In 2000, the ST/MO group concentrated its efforts to support the last year of LEP running. The TCR monitoring system was rationalized and the operation procedure has started to be rejuvenated.

Technical Support Division 279 Two major contracts were elaborated to support the CERN safety and technical monitoring activities. At year-end, a re-organization of the group took place, with a view to clarifying the group work axis: operation, industrial computing, safety system, and administrative computing.

Several recruitment actions were necessary to complete the number of operators required by the TCR rota, and to reinforce the group competencies in the database field.

Technical Control Room (TCR)

The number of actions recorded by the TCR operation crews increased by a factor of 10%, at around 12 000. The direct on-site interventions made by the operators outside normal working hours remained the same, with an average of three interventions per eight-hour shift at a level similar to the past.

During 2000, replacements for three operators had to be found. The new operators will be trained and incorporated into the team during winter 2001. In 2000 a particular effort was focused on improving the quality of the information monitored by the operators as well as the number of supervised alarms.

A project to improve the restart of the general services used by the accelerators after major incidents was launched in collaboration with the PCR. It should improve the documentation, procedure, and software tools used by the TCR. It will also define a new operation method necessary for the LHC monitoring.

Computing Support

The specification of the future CERN Safety Alarm Monitoring System (CSAM) was written. The call for tender was released and the answers analysed, leading to the signature of a contract in March 2001.

A contract to outsource part of the ST Division Industrial Controls activities was specified and submitted to the competitive tendering procedure. It is now ready to support the software developments and maintenance activities of the division.

The Industrial Computing section has actively worked to rationalize and improve the reliability of the TCR monitoring system. A new service was put in place to manage the requests for equipment supervision made to the TCR; this service is named TCR Control Desk (TCD). A renewal plan of the group database activity was set up and is being carried out.

The EREM project aiming at the replacement of old data acquisition equipment (ECATCR) with industrial PLCs is following the planned timetable and shows reliability improvement. Eighty per cent of the equipment has already been replaced. The TIM project has actively co-operated with the LHC Controls Project to define the LHC monitoring needs. In this context, the use of the CERN-recommended SCADA has been prototyped in collaboration with the EP, SL and IT Divisions.

Support was also provided to several groups of the division particularly for the design of safety-related control systems, contract follow-up, and administrative tool development and maintenance such as the Authorization Management System.

280 Technical Support Division The desktop support was relaunched, as well as the support to the EDMS documentation management system.

Extensive support was provided for the migration of the divisional maintenance management system to the new MP5 tools.

Technical Facilities Management

The Technical Facilities Management (TFM) group is responsible for managing and performing technical work (civil engineering, electricity, air-conditioning, heating and cooling, etc.) on the surface structures and infrastructure not connected with the accelerators, i.e. new work, renovation and conversions. The group is also responsible for maintaining the corresponding structures and technical equipment. It updates the data relating to the Organization’s property and drawings and also handles grounds maintenance and the cleaning of buildings and halls.

Work Performed

The group handled many projects in 2000, of which those mentioned below were particularly significant in terms of cost, duration and complexity of the implementation or technical co-ordination work involved.

– Anti-carbonation treatment of Bldg. 274.

– Asbestos disposal of Bldgs. 274 and 893.

– Construction of a 680 m2 metal/fabric structure to be used for storage purposes (Bldg. 610).

– Transformation of cafeteria Bldg. 504.

– Renovation of terraces Bldgs. 501 (200 m2) and 504 (400 m2).

– Work to enhance safety in the Main Building (Bldg. 60): fire detection and safety of people.

– Re-fitting of 3000 m2 space in the ISR tunnel for storage of SPS/LEP equipment.

– Replacement of obsolete electrical switchboards.

– Air-conditioning (5th floor, Bldg. 40).

– Re-fitting of basement of Bldgs. 3, 58 and 51.

– Asbestos diagnostic checks in the buildings on the Swiss part of the CERN site.

Current and Future Design Studies and Projects – Construction of a 600 m2 structure to be used for supermodules for CMS (Hall 947).

– Construction of a 1600 m2 metal/fabric structure to be used for storage of ATLAS equipment (Bldg. 609).

– Transformer pits BA4.

Technical Support Division 281 – Conversion of the dishwashing tunnel in Restaurant no. 3.

– Asbestos disposal, Bldg. 863 (BA6).

– Re-fitting of the two floors of the Medical Service (Bldg. 57).

– Re-fitting of hall for ATLAS experiments (Bldg. 191).

– Renovation of Bldg. 182.

– Renovation of all the lighting in the Auditorium (Bldg. 60).

– Construction of building for data storage ‘robots’ for IT Division (Bldg. 613).

Several projects required design studies involving calculations on existing structures and buildings. For this work the group used a contract with an outside civil engineering consultant.

Project Management Support Section

The Project Management Support section is the interface between the divisions and the TFM Group sections. The Section makes a precise definition of projects in order to get them off the ground and subsequently handles the technical and financial follow-up. It ensures that the project data (technical and financial developments, deadlines, etc) are updated in real-time.

The Section handled around 20 projects, the average cost of each was around 450 kCHF.

Works Section

The Works section is responsible for managing work requested by users in the fields of electricity, civil engineering, air-conditioning and heating (preparation, execution, follow-up, etc.).

The Electricity unit managed electrical installation work (around 420 operations), 70% of which are minor tasks requested and paid for by the users. These essentially relate to lighting and power circuits. The unit is also involved in all the major overall renovation work (offices, laboratories, halls, etc.). This involves extensions to and replacement of existing installations and equipment to meet safety requirements (elimination of PVC cables, obsolete circuit-breakers, etc.).

The Civil Engineering unit carries out adaptation of structures and networks which are financed from ‘project’ budgets. These consist of projects covered by users’ or the divisions’ budgets and co-ordinated by the group (space reorganization, improving safety of existing infrastructures, new computing rooms, clean rooms, etc). The Civil Engineering unit managed about 250 work requests.

The Heating and Air-Conditioning unit carried out 95 work requests.

282 Technical Support Division Site Maintenance Section

The Site Maintenance section performs maintenance, operation and repairs on all CERN property and technical facilities of the surface infrastructures.

For the Civil Engineering unit, these operations essentially relate to remedial work on the sewers and drains, road surfaces and car-parks, clear and waste-water networks, indoor public areas, façades, etc. Around 2300 interventions of repair work, undertaken by different contracts, took place. The unit undertook a number of ‘consolidation maintenance’ projects in order to tackle recurrent problems (waterproofing of roof-tops in general and electricity substations in particular).

Several consolidation work studies were carried out, some of which led to work which has now been completed: renovation of the heating installations in Bldgs. 3 and 304, renovation of air-conditioning plant in Bldg. 30 (auditorium, lecture room, cafeteria, etc.).

The Heating and Air-Conditioning unit conducts and manages all its maintenance activities, minor works and repairs (some 1400) by a cooling–ventilation contract.

The Electricity unit is responsible for equipment maintenance and supervises the repair operations (some 2600) undertaken by an electrical services contract.

The fourth phase (2000) of the project to replace the electrical distribution switchboards was also carried out; this is challenging work in terms of preparation and safety.

Patrimony Data and Drawings Section

The Patrimony Data and Drawings section is a service providing ‘users’ with information and documentation relating to CERN’s buildings and general facilities on all types of media (paper, tracings, computer file, microfilm, etc.).

It has to update the 65 000 drawings for which it is responsible and introduce any amendments (extensions, modifications to an existing structure, new buildings, etc.).

The section has launched, over the last three years, a modernization programme with the aim of providing computerized documents. The migration of the MICROSTATION database into the SIG (Graphical Information System) STAR was completed in February 2000. Currently, two new Sun workstations are being formatted which, at the end of 2001, will allow the management of this database. The users will be able to access this data directly from the Web.

Scanning of archived plans and drawings is well advanced. For the moment, almost 35 000 plans have been scanned in TIF format. They are accessible from the Web via CDD (CERN Drawing Directory).

The GEOSIP database on Oracle is permanently updated. The data contained in these tables are used by the divisions and also by CERN’s property insurance.

Technical Support Division 283 The feasibility studies for preliminary projects such as SPL and the neutrino factory are settled by the GP section.

Environment Section

The section has in charge the cleaning of CERN premises, roads and carparks, collection of waste, and landscaping. It operates result-oriented industrial services contracts.

The grounds maintenance contract covers work and maintenance on the 120 hectares of the CERN site, with scheduled maintenance performed on 70 hectares.

Concerning waste disposal, more than 2100 tons of all types of ordinary and special wastes are despatched annually to outside processing plants for treatment. Other, organic, wastes are directly treated on site.

The service also provides important technical support to the three restaurants with regard to the layout and safety of their internal infrastructure and restaurant equipment.

Contracts

Work is performed through 19 industrial service contracts; a market survey has been launched with a grouping together of nine of these contracts covering civil engineering work into a single contract (masonry, painting, steel structures, floor coverings, etc.). The call for tenders should be finalized by spring 2001. The beginning of the new contract is foreseen for early 2002.

284 Technical Support Division Technical Inspection & Safety Division

Radiation Protection Group

In 2000, as in previous years, the regular work of radiation survey of facilities and experiments, the personal dosimetry service, radioactive waste management, and the radiation assessments of future facilities and experiments was the fundamental part of RP activities. However, LEP dismantling under INB rules, new experiments such as nTOF and CNGS as well as acute issues in radioactive waste management and the necessity to establish a new procedure for individual neutron monitoring created substantial additional work for the Group.

In preparation for LEP dismantling, the induced radioactivity in the various materials of the entire LEP installation had to be assessed. In a continuation of earlier work, Monte Carlo calculations were performed and gamma-spectrometry measurements on materials (e.g. dipoles, cable-trays and tunnel walls) were carried out to validate the calculations. Earlier reference data were confirmed and a report submitted to the French Authority (DSIN). This report is the basis for distinction (‘zonage’) between radioactive (predominantly weakly active = ‘Très Faiblement Actif’, TFA) and non-radioactive (conventional) material during dismantling and disposal of LEP components. The RP Group is actively involved in surveys during dismantling and has installed a sensitive radiation monitor on the surface at the Prévessin site so that lorries carrying nominally conventional material from dismantling can be checked when leaving the site.

The preparation and commissioning of the nTOF facility required a significant involvement of the RP Group. In view of the future very high activation levels, a reliable remote target transport and handling system had to be installed and the target cooling system had to be modified to meet radiation safety requirements. In November, the commissioning established that the facility met relevant radiation safety regulations. However, further issues, in particular the future handling and storage of the activated target(s) as waste have still to be addressed.

Radiation safety studies for new and future installations concentrated on the LHC, CNGS, CTF3 and AD facilities. With regard to the LHC the aspects included shielding considerations for LHC start-up, radiation constraints from induced radioactivity in the design of the LHC facility, radiation protection precautions during the construction of the LHC injection lines. Another emphasis was on the assessment of the environmental radiological situation to be expected around the LHC facilities. For the CNGS facility, the effective dose to members of the public due to the release of radioactivity in air was calculated. Measurements in the AD target area were made to validate calculations, in particular with regard to dose rates associated with the use of the AD’s low-energy antiproton beams.

Technical Inspection & Safety Division 285 During the year, a more fundamental approach towards radioactive waste management at CERN was initiated. This included the establishment of an inventory of radioactive waste and (recyclable) material, an analysis of disposal pathways and the costs and first steps towards a new CERN waste policy. It appeared that CERN must establish a state-of-the-art interim storage facility with an adequate waste conditioning facility; effective waste disposal pathways have to be set up and new facilities and experiments must be optimized systematically in order to reduce future radioactive waste to a minimum.

While this conceptual work is in progress, the handling, conditioning and storing of current waste had to continue. The considerable amount of additional waste coming from LEP dismantling and the related ‘dismantling’ of SPS components marked the year 2000 (as it will 2001). In the ISR, an additional 1000 m2 of storage area had to be refurbished as interim storage space in such a way that it meets the criteria of an INB storage facility.

National waste storage facilities as well as INB rules will require identification and tracking (‘traceability’) of each item, including specification of the radioactive nuclide inventory. As a step towards establishing tools for that purpose, the RP Group created a questionnaire to be completed for each waste item and a database. This will have to be complemented by the development of calculation tools to determine the nuclide inventory and adequate experimental verification methods.

During the year a fundamental change in the operation of the personal dosimetry service was initiated. Technical considerations (the currently used neutron personal dosemeters will no longer be commercially available) as well as operational and regulatory aspects have led to the conclusion that the provision and evaluation of personal dosemeters should be carried out by an external company in the future. For neutron personal dosimetry this will start in April 2001 and the supply of the entire personal dosimetry is scheduled for mid 2003.

The Calibration Laboratory for radiation monitors has continued the process for accreditation according to the international standard ISO 17025. An inventory database for all radiation protection instruments has been created.

A total of 112 tons of depleted uranium (DU) stored in Bldg. 955 were removed, packed, and shipped to the USA. The EP Division handled the overall organization; the RP Group provided the radiation protection supervision. It is anticipated that more DU will leave CERN in 2001.

As in previous years, the CERF facility (which simulates cosmic-ray radiation fields at about 10–12 km altitude in the atmosphere) was operated by the Group for two runs and used by participants from several European countries.

An incident at the front-end of ISOLDE caused minor contamination of two persons. Analysis revealed exposures of less than 1 mSv each. In order to improve the safety installations of ISOLDE, in collaboration with TIS-RP, PS Division has initiated a safety consolidation programme for the experiment.

286 Technical Inspection & Safety Division General Safety Group

The main goal of the Safety Inspection and Ergonomy Section in 2000 was to consolidate the efforts to improve safety inspections by computerization of reports, redefinition of mission, standardization of templates, etc. Compared to previous years, action was taken more often and more rapidly after the safety visits. As to the LHC work site there were still some complaints from local inhabitants on account of sporadic excessive noise emissions, even after the creation of acoustic walls on most construction sites. Work continued on a computational fluid dynamics study on the accidental spill of liquid argon in the ATLAS cavern. An experiment was carried out in the West Hall, the results of which increased the confidence in the computer model. In addition to these main activities, all safety equipment sold via the CERN stores was re-examined and upgraded; safety documentation was completely renewed; new circuits for CERN visits were studied following the closure of LEP; the organization of several artistic performances on the CERN site by ETT Division provided the opportunity to define a new policy for such events. Work accidents were followed up as in preceding years, but data are preliminary, because the lost days are not yet precisely known.

Preliminary statistics of professional accidents in 2000 (CERN staff only)

Total declared accidentsa) Number Lost days

(i) Accidents in total 23 692

(ii) Road accidents on the journey to or from CERNb) 2 48 b) Road accident within CERN 1 43

a) Accidents entailing at least one day’s absence from work. b) Lost time included under (i).

The Gas and Chemistry Section dealt with the identification of asbestos in buildings on the site in collaboration with ST Division. It monitored the safe removal of asbestos during maintenance work and the protection of personnel and the environment, particularly in Bldgs. 3 and 60 and in the PS ring. A survey of the CERN Meyrin site was carried out to identify areas with contamination by PCB. The results showed that the concentration is such that CERN does not need to be declared a contaminated site according to the existing laws. Safety training was continued for persons using gases and chemicals, and arrangements were made for future safety training needs. Water pollution problems at several of the LHC work sites were controlled and rectified in collaboration with ST-CE. Work on the preparation of the 3rd High Energy Physics Technical Safety Forum at Fermilab in May 2001 began.

The main activity of the Electrical Safety Section was the periodical inspections and receptions of electrical power and distribution systems (3.3 kV safety networks). The updating of safety instructions and notes was continued (IS5 ‘Emergency Stops’, IS48 ‘Fire Prevention for cables, cable trays and conduits’, NS24 ‘Procedures for dismantling unused electrical cables’). Project-oriented counselling (CMS coil power supply) and risk assessment by means of a new electrical risk database were continued. The section consulted on the CERN safety alarm-monitoring project (CSAM) and contributed to its functional safety analysis. Work concerning measurements of exposure to electromagnetic radiation for large office buildings (60, 30) and accelerator installations (compensating coils) has started. Training courses were held on electrical safety recycling (habilitation), electrical safety for Territorial Safety Officers (TSOs), and on electromagnetic radiation in the frame of the summer student lectures.

Technical Inspection & Safety Division 287 The Fire Prevention Section took part in several working groups on risk analysis for components of CMS (Preshower) and ATLAS (Fire and Gas inside ATLAS). The fire detection requirements for the LHC surface buildings were defined in collaboration with ST Division and the owner divisions. Tests were carried out on the application of extinguishing and detection concepts for the experiment halls (high expansion foam test, mobile radio fire detection systems). An upgrade of the fire protection has been suggested for Bldg. 54 and a similar project is being accomplished for the Main Building. Fire detection and ventilation/smoke extraction systems in the LHC surface buildings were tested, in collaboration with ST Division. Evacuation exercises were performed for public buildings (kindergarten), office buildings (30) and for those presenting a particular risk (galvano-plastic and chemical polishing workshop, underground experimental areas) in collaboration with the divisions concerned and the Fire Brigade.

The Civil Engineering and Contractors Section followed the integration of safety aspects into major projects such as the LHC and CNGS. The concept of safety co-ordination is divided into two categories of work as defined by the Safety Regulations. Several large projects such as LHC, CNGS, the storage building for radioactive material, and the water project belong to the 1st category and are as such followed by trained and certified safety co-ordinators from external certified prevention companies. For the 2nd category of work concerning maintenance, industrial support or installation contracts, ST and EST Divisions started with the aid of TIS to draw up risk prevention plans. A LEP machine and experiments dismantling safety report was finalized and safety protocols drawn up. The section accompanied several projects such as the upgrading of the Main Building, and the renovation of lifts and other buildings (extension of computer centre and cooling towers).

With regard to the Safety for LHC experiments, members of the group participated as reviewer at several design reviews of ATLAS (grounding, cryogenic, gas and laser systems) and CMS (electromagnetic calorimeter, tracker and forward shielding). The TIS working group for LHC safety dealt with topics of various types. It co-ordinated fire tests on halogen-free laminates for printed circuit boards. The integration of the three safety co-ordinators for dismantling of LEP and the installation of LHC was achieved.

Technical Services and Environment Group

During the past year the activities of the Mechanical Engineering Section were mostly related to the LHC project. The structural safety of numerous components of the LHC machine was assessed, recommendations were given and designs approved. A great deal of work was again this year related to the ATLAS and CMS experiments while the amount of work on LHCb and ALICE became significant. The members of the section contributed actively to Engineering Design Reviews and to finalizing Technical Specifications. The section also ensured the follow-up of two Memoranda of Understanding which cover the United States in-kind contributions to the LHC machine and to CMS. Extensive work was also carried out on regulatory issues: specifically on the application of Seismic Codes and Metallic Structures Codes. Substantial practical guidance and support was given to different users for their analyses. The section also started and completed, as a pilot project, the migration of documents to an EDMS database. This database will be tested in 2001.

The Mechanical Inspection Section carried out reception tests and routine inspections on pressure equipment, safety valves, and lifting equipment. The first set of lifting equipment for the LHC was tested, while the periodic inspection programme resulted in more than 1600 items of lifting equipment being checked

288 Technical Inspection & Safety Division as well as more than 4000 items of ancillary equipment. The programme to bring CERN pressure equipment into conformity continued: 140 vessels were checked. Final reception took place of the 12 helium storage tanks of 250 m3 volume, and more than 1750 safety valves were checked and, wherever needed, brought into conformity with the safety regulations. Training of welders and of lifting equipment operators was ensured. Developments of pressure testing in limiting conditions were carried out, with tests on samples carried out in the test bunker. A study on a quality assurance plan was launched. The machine tools conformity programme advanced well, although its completion was postponed into 2001 since a number of tools were not declared when the programme was launched.

The Materials and High-level Dosimetry Section continued to help CERN groups in selecting safe materials for the LHC machine and experiments. The main open point is still the replacement of brominated laminates used for the printed circuit boards; only four suppliers have been identified, two European and two Japanese. The reliability of the new halogen-free materials has not yet been proven. The cable-controller also continued the checking of all purchase orders for cables. Apart from the 40 km of special water-resistant optical cables to be used in outside trenches, and the PTFE insulated wires to be used in LHC cryostats, about 99% of the cables entering at CERN respect the very severe CERN safety standards. Thanks to its knowledge of the radiation behaviour of organic materials, and to the high-dose dosimetry programme, the section provided information to users about the lifetime of their equipment in the machines. This was particularly appreciated in the LEP machine, the energy of which was increased to its maximum, and in the PS complex in view of the projected increase of beam intensity.

In 2000 the routine environmental monitoring programme was conducted smoothly and all reports were issued on schedule. The conventional monitoring programme of the Environmental Section was further extended by adding the monitoring of the physical and chemical parameters of water in rivers receiving water from CERN. The number of traditional measuring points was increased with the addition of checkpoints for civil engineering work sites related to the LHC project. At the end of the year another technician was recruited in the section to cope with the increasing duties of the routine monitoring programme. The feasibility study of the implementation of an environmental management system at CERN, which was started in 1999, culminated in a presentation of its results to the management of the Organization, which resulted in its acceptance. During the year several technical developments took place, and a quality assurance programme for gamma spectrometry was implemented. The section was also involved in the planning of the ‘Point Zero’ measuring campaign, which will be carried out by the French and Swiss authorities before the start-up of LHC.

The Technical Support Section was mainly concerned with installation and testing of equipment for the Radiation Protection Group and with the upgrading of the site monitors for the TIS-TE Environmental Section. A radiation monitoring system for the nTOF experiment was designed, installed and commissioned. The specification for a highly sensitive radiation monitor to be used in the dismantling of LEP accelerator was elaborated and adjudication was carried out after a call for tender. This monitor was then installed, within a tight schedule, at the exit of the transit zone on the Prévessin site. Close liaison and discussions with the manufacturer enabled a series of acceptance tests to be satisfactorily completed. Studies were made to enable the relocation of all the LEP Area Controllers to the Site Access buildings after the closure of the LEP accelerator. The upgrading of all gate monitor systems was continued and two new detectors were installed and tested. New induced-activity monitoring systems were prepared for installation in the LSS2 and LSS6 areas of the SPS accelerator. The dosimetry system for the on-line radiation damage tests for the components of the LHC in TCC2 was adapted and commissioned for the irradiation period in 2000. Studies were made on

Technical Inspection & Safety Division 289 the radiation and environmental monitoring system for the LHC accelerator and a field-bus-based evaluation set-up was constructed. The New Rover radiation survey equipment was upgraded. The section supervised the contract in force with the Desktop Support Service for printers and personal computers, although it was still necessary to give a reduced level of local support.

The Software Support Section managed to continue to ensure operation of the Radiation Protection data acquisition and monitoring system and to improve several elements of it. Moreover, the section redesigned and restructured the database for individual dosimetry, maintained other Radiation Protection ORACLE database applications, and started restructuring and reconstructing the CERN Medical Database. The TIS safety documents were made available under EDMS. In addition, the team maintained several Web pages, participated in interdivisional meetings, and provided general software support for users at TIS.

Medical Service

The Medical Service pursued its usual objectives throughout the year 2000, on the basis of a medical check-up every two years for all CERN personnel. Consequently, the two doctors carried out 2816 medical consultations; the number staying stable compared to previous years.

Concerning the individual analysis of workstations and occupational hazards, 70 workstation visits made it possible to gain a better understanding of working constraints and 1500 new occupational hazards questionnaires were updated during the medical consultation. The occupational hazards questionnaire forms an integral part of the member of personnel’s medical file and makes it possible to trace each workstation throughout a person’s professional career.

At the level of the infirmary, 2266 complementary examinations (ECG, thorax X-ray, sight test, hearing test, respiratory test) were carried out to determine medical aptitude, within the framework of a private consultation or at the time of a medical emergency. More than 400 people benefited from first-aid care following an occupational accident; in more than half of the cases it concerned personnel from outside companies.

Concerning the examinations carried out in the laboratory, a big effort was made to increase the number of biochemical check-ups, particularly in the pre-employment category: 1002 in the year 2000 compared with 892 in 1999. The total number of blood tests carried out represents 2804 haematological check-ups and 1494 verifications of medical certificates of aptitude to work in controlled radiation areas.

The information campaign for better medical follow-up of Users bore fruit as more than 900 medical certificates of the model requested were sent to the Medical Service, which represents an increase of approximately 15%, compared to 1999.

In addition, during the year 2000 two public awareness campaigns mobilized the whole of the Medical Service:

– a day of prevention and screening for hearing problems: almost 125 people came to the Medical Service on March 7th to pass a hearing test. As a result of this test, 34 people were recommended to follow specialized treatment;

290 Technical Inspection & Safety Division – public awareness days for the handling of heavy objects: around 100 people were shown the correct handling gestures to use in the workshops, as we see a significant number of back problems in this professional category.

Fire Brigade

The year 2000 was marked by significant changes in the organization of the Brigade. During the second half of the year, three people, heads of important units within the Brigade, retired. Two other members were reclassified for health reasons and therefore left the Service and unfortunately one member of the service died.

The main change has been the reduction of the day team, from 10 to 7, in order to increase the number of operational personnel on shifts. Two new positions, for operational assistants, were created to reinforce the intervention capacity of the teams whilst giving important support to the technical work of the day team. As a consequence of this and on account of our detachment system, the second half of the year was marked by an intense period of interviews in order to select new personnel. Nine firefighters start a new term of three years’ detachment in February 2001 and two operational assistants will start in March 2001.

Concerning the daily work, the main change was the revision of the night activity of the teams by converting the night rounds into instructional visits to buildings and installations and the revision of the intervention plans.

The number of interventions (1599 in all) decreased by approximately 25% compared to those recorded in 1999, mainly owing to a reduction in automatic alarms of almost 30%. The number of emergency call-outs followed by fire and rescue operations also decreased slightly (see attached table). No major incidents happened during the year. The most significant interventions were a transformer fire in BA3, a fire in the ventilation system of the SPS at BA6, a small fire of uranium pellets in Bldg. 3 that resulted in exhaustive contamination control procedures, and an intruder in the PS control room that ended with his being arrested by the Geneva Police. Five pollution incidents (the same number as last year) and five incidents involving radiation were dealt with. The only activities that have increased compared to previous years are lost property and theft declarations, and the number of ‘taxi’ transports. No important incidents due to extreme weather conditions were recorded.

The LEP shutdown ceremony in October posed an important challenge to our Brigade as we had a key role in the organization and co-ordination of safety during the event. This involved the French fire brigade, two rescue helicopters and the ambulance service. In addition to the normal resources, 14 CERN firemen reinforced the safety crews for the event.

Relations with the neighbouring fire services of the host States were maintained at a satisfactory level. A series of meetings were held which resulted in an outline programme being agreed for closer ties between the CERN Fire Brigade and the Fire Service of the Département de l’Ain and visits of CERN installations were organized for 50 officers. These will continue in 2001. Furthermore, agreement was reached to ensure basic and continuation training in rope rescue skills (GRIMP) in 2001.

Technical Inspection & Safety Division 291 On the Swiss side of the border the close working relationship continues. Geneva Fire Service recruits were trained in CERN’s fire simulator and CERN’s underground installations were used as a training venue. This was very successful and will continue in 2001. Crews from Geneva Fire Service carried out site familiarization visits. A collaboration agreement was reached with the Neuchâtel Fire Service enabling the CERN Fire Brigade ambulance staff to gain practical experience by attending emergency interventions in Neuchâtel. This will be in exchange for fire simulator training at CERN.

A series of (3) small exercises were organized on the LHC civil engineering projects to confirm the CERN Fire Brigade intervention procedures and response time. A new four-day Command and Control course was introduced to better enable incident commanders to understand and apply the decision-making logic used during emergency interventions. The four watch instructors received training in Sweden and Finland to better enable them to train our own people and exterior firefighters in CERN’s flashover simulator.

During the year, 1950 people attended a basic CERN safety-training course. LEP dismantling and LHC civil engineering projects were the main reasons for the 50% increase. Courses were also provided for summer students and CERN guides from the Visits service. Assistance was given to the latter to define rules for the safe conduct of the new, post LEP, visit itineraries.

The French courses given for the detached firefighters have continued and the Service continues to provide English courses for some of its staff. The database of the service was optimized to improve access to intervention reports and statistics. The Administrative Circular No. 25 that defines ‘Special provisions for the Fire and Rescue Services’ has been revised and is ready to be submitted for approval.

Regarding equipment, in September a new ambulance replaced a 16-year-old one and a new container was acquired with specialized equipment for interventions involving hazardous materials and for a command post for major interventions. We have accomplished all the administrative and technical procedures for the acquisition of a new fire truck that will replace an 18-year-old one.

The expected qualitative and quantitative increase of the risk of accident at CERN due to the demanding activity of the dismantling of LEP and the installation of the LHC, has highlighted the need for an auxiliary fire service.

292 Technical Inspection & Safety Division Summary of Fire Brigade Activities

1st qr. 2nd qr. 3rd qr. 4th qr. Interventions 2000 1999 1998 1997 2000 2000 2000 2000 Call-outs 71 86 81 72 310 367 367 309 Ambulances 36 42 40 41 159 195 173 163 Fires 7 8 6 2 23 23 25 17 Water leaks and flooding 21 21 17 17 76 109 118 84 Problems due to animals 5 6 15 5 31 26 36 30 Radiation incidents 1 1 0 3 5 – – – Chemical incidents 0 4 3 4 11 9 13 6 Pollution incidents 1 4 0 0 5 5 2 9 Automatic alarms 230 165 216 206 817 1142 1412 1509 Fire detection 93 102 122 117 434 588 725 760 Gas detection 9 9 13 18 49 52 92 73 Emergency stops 4 3 1 3 11 11 17 27 Evacuation alarm 4 4 3 1 12 – – – Dead man alarm 0 0 0 3 3 – – – General alarms 1 1 0 5 7 7 12 6 Flood detection 6 1 12 3 22 20 23 26 Oxygen detection 2 1 10 3 16 – – – Lifts 107 40 51 50 248 431 475 556 Intrusion alarm 4 4 4 3 15 33 68 61 Direct prevention 40 28 25 37 130 145 178 114 Monitoring of confined spaces 31 17 12 26 86 99 148 83 Supervision of hazardous work 0 1 7 0 8 3 5 10 Machine inspection rounds 2 0 0 0 2 2 1 4 Traffic accident reports 7 8 6 11 32 30 24 17 Felling of dangerous trees 0 2 0 0 2 11 0 0 Logistical support 31 36 48 38 153 215 187 139 Opening/locking of buildings (access) 8 16 22 12 58 81 74 33 Opening of customs tunnel 1 6 7 1 15 16 15 19 Special guards 4 3 2 10 19 30 14 11 Opening of stores 2 2 4 2 10 10 23 5 Breakdown 16 9 13 13 51 78 61 71 Miscellaneous 45 52 64 28 189 349 309 387 Total interventions 417 367 434 381 1599 2218 2601 2602 Equipment control and maintenance 332 324 309 287 1252 1535 1739 1790 Transports ‘Taxi’ 60 84 123 97 364 252 340 313 Declarations of loss and theft 130 176 169 130 538 406 233 236 Exercises 21 24 15 6 66 98 148 144 Found object declarations 17 15 20 15 67 43 – – Total activities 977 990 1070 916 3886 4552 5061 5085

Technical Inspection & Safety Division 293

Engineering Support and Technologies Division

Introduction

Since 1996 the Engineering Support and Technologies (EST) Division has offered support to the whole of CERN, not only with mechanical technologies, but also with prototyping of electronic circuits, database applications in engineering and project management, experimental areas and the experiment–machine interface of the LHC, as well as alignment and survey activities. The Division runs centralized CAD-based mechanical design offices and production workshops, and also specialized workshops and laboratories for materials and surface studies. The main focus of work in 2000 continued to be for the LHC project, both for the accelerator and experiments.

The Division was structured in eight groups with a total permanent staff of around 225. There were 15 departures during the year, of which nine were early retirements and seven new arrivals were welcomed. A proposal to centralize further the electronic layout and printed circuit board services of CERN by combining an EP Division service with a section of the EST-SM group resulted in a transfer of nine staff from EP to EST at the end of the year and the creation of a new DEM group in EST Division as of 1 January 2001. Two other EST staff members joined ST Division to strengthen the team working on cooling of electronics for the LHC experiments.

In addition to the staff mentioned above, EST has an average of some 50 fellows, associates, trainees and students working in the Division as part of the CERN training programme. With most of them staying nine months or longer, they also represent a greatly appreciated contribution to the total work force of EST. In addition, several industrial support contracts of different types are managed by EST and these supply a total of 200 full-time equivalents (FTEs), of which some 120 were required in the mechanical workshops and design offices last year.

With an exploitation budget of about 5 MCHF and a cost of industrial support of about 15 MCHF, most of the technical services offered to other divisions and clients were invoiced to cover the cost of contracts and job related materials. The invoiced total in 2000 was 16.3 MCHF. In addition to providing services, the Division carried out project work for 5.5 MCHF of which 3.7 MCHF was for the LHC machine and experimental areas.

More detailed information of the year 2000 contribution of each EST group is given below.

Engineering Support and Technologies Division 295 Administration and Planning

The Administration and Planning (DI) Group is in charge of all the general divisional administration including not only the secretarial support for EST groups, but also the planning of resources, budgets, accountancy, staff management, and the maintenance of the general infrastructure of the Division. The DI group also provides administrative support for the Divisional Safety Officer (DSO) and the Divisional Training Officer (DTO).

Secretariats

The administrative and secretariat work of EST was shared among the seven secretaries in the Divisional secretariat and five local group secretariats. In addition to the usual large number of standard documents, such as minutes, conference papers, technical notes and specifications, some special documents had to be produced in the course of 2000, in particular the accident prevention plans for large contractors. The publication of the minutes of important meetings and reports on the dedicated Web servers required the use of new text processing techniques such as the conversion of files under PDF format and WWW links. The archiving of paper versions of EST and older MT division documents has progressed well and the electronic archiving of EST technical documents in EDMS has started. In parallel new administrative procedures were introduced, including the new leave management system based on EDH.

Human Resources and Infrastructure

The Human resources and Infrastructure Section managed the 225 staff members of the Division. The integration of new staff members and the administration for members of the personnel leaving in addition to the usual changeover of more than 100 different scientific associates and visitors added to this work load.

The section also handled a number of maintenance, conversion, or consolidation tasks for EST offices, laboratories and halls, the cost of which reached 200 kCHF; among them the installation of a press for the production of base boards for ATLAS detector electronics and repair work on retention tanks for the surface treatment plants.

The installation of evacuation alarms was completed in several buildings in order to comply with legal obligations in Switzerland (‘Ordonnance suisse sur la Protection contre les Accidents Majeurs, OPAM’).

Budget and Planning

Support for the management of various industrial service contracts and development to more and more result-oriented tasks as well as support for the management of the invoicing to user groups and the follow-up of the EST groups’ expenses are another important task of the DI group. In 2000 it was still possible to maintain the hourly rates for internal invoicing at the level of 1999, but a growing imbalance became apparent at the end of the year in the areas of mechanical design and workshops.

296 Engineering Support and Technologies Division Engineering Design Offices

The support activities for mechanical engineering and design are shared by two groups: Engineering Support for Infrastructures (ESI) and Engineering Support for Machines (ESM) totalling about 50 staff members, 45 contract personnel and six visitors. The two groups had increasing difficulties in satisfying the requests of all their clients in 2000, due to a continually increasing demand and decreasing CERN staff numbers. During 2000, only one young staff designer arrived while four retired. A design support contract (Franco-German) has been operating since mid 1998 and drawing work is sent off-site to three firms in Great Britain, Spain and France. A new call for tender for design support at CERN from 2002 onwards will be issued shortly. For urgent needs, designers from the local region have in the past also been hired on temporary labour contracts; however, in line with French labour laws, this type of manpower will in the future only be used for short-term replacements.

The LHC Quality Assurance Plan is now operational in mechanical design, with clear rules for checking, approving and releasing drawings for execution, as well as support for systematic design reviews before tendering and production in industry.

About 70% of the design work in EST is carried out with AutoCad software on PCs (version 14 for Windows) and 30% with EUCLID software using UNIX workstations. The EST design groups co-ordinate the use of both AutoCad and EUCLID software CERN-wide (CASC Committee), and are actively participating in the co-ordination of Mechanical Computer Aided Engineering at CERN, through the CAEC Committee.

During the first half of 2000, the groups of LHC, PS and SL Divisions were asked to update their forecasts for design needs in the coming two years. The result was the usual profile of increasing needs over the following 6–9 months, but also a number of new requests exceeding the available capacity in 2001 and 2002. ESI and ESM do their best to achieve, in close collaboration with the design support contractor and project, group, or division leaders concerned, a more dynamic sharing of the workload, a more transparent planning and faster completion through a tighter control of changes. A database, available to users on the CERN network, gives all the relevant information for the more than 200 design jobs handled at any one time by the EST design groups.

Engineering Support for Infrastructure

The ESI Group provides engineering support for mechanical design centred around machine layouts, PS activities, selected LHC components, and infrastructure for the LHC experimental areas and experiments. Specialities are steel structures, heavy handling, robotics, mechanical calculations and measurements, design of ultra-high-vacuum equipment, and beam instrumentation.

Accelerator Components and Instrumentation

During the year 2000 only a limited design support for LEP was required, mainly for the last version of the high-precision beam energy measurement spectrometer.

Engineering Support and Technologies Division 297 A considerable and growing effort was devoted to design studies of the LHC components and instrumentation. The design of the LHC experimental vacuum chambers, as specified by the LHC vacuum group, has advanced and in some cases been validated by full-scale test segments. During the year an intensive four-year programme of the design work for LHC beam instrumentation, defined by the SL beam instrumentation group, was started, resulting in first instruments being produced and prepared for tests.

Finally, in response to the requests of LHC magnet and cryostat engineers, the ESI group provided additional special support for the design of the interconnects for the main lattice magnets.

Support to Experiments

Support to the LHC experiments included design work for the integration of services in the ATLAS and ALICE detectors, as well as participation in the design of the ATLAS forward shielding. The design of steel structures supporting the ATLAS muon chambers was reviewed and modified in accordance with new load requirements

The group continued its limited support for the COMPASS project, by participating – after design studies and follow-up of manufacture – in the installation and testing of the ultralight aluminium supporting structure for the semitransparent mirrors of the RICH detector.

Activity Linked to the PS Complex

Design work linked to the transformation of the PS machines for use as an LHC injection complex, notably for new septum magnets, is almost finished and the layouts which include new components have been updated. The design work for the Antiproton Decelerator (AD) project, completed in 1999, was restricted to consolidation. The RFQ decelerator, designed with a substantial contribution from the ESI group, was successfully tested and installed. Some design support for CLIC and the CLIC test facility, CTF3, as well as for the Laser Ion Source (LIS) experiment continued and the 1999 design task for the neutron Time of Flight (nTOF) project – the injection line and target zone – was completed.

Infrastructure for the LHC

The design work on steel supporting structures for the LHC experimental zones, underground caverns, shafts and tunnels, terminated in 1999 with respect to major structures, continued quite intensively through 2000, including new structures for ALICE and tunnel zones and several modifications notably for ATLAS. These new structures increase the estimated total mass of the LHC steel structures to 1300 tonnes. A review of the installation scenario of the structures resulted in a more rational installation sequence, the revised schedule now requires the call for tenders to be sent out early in 2001.

The effort devoted to the production of integrated 3D installation layouts for the LHC accelerator and its experimental zones was intensified, with increased participation in the work of various LHC working groups (Transport WG, Underground Installation Layouts WG, and ATLAS, CMS and ALICE experimental zones). With the steady progress of the LHC project, this design work – essential for a final verification of the

298 Engineering Support and Technologies Division integration of LHC components in the tunnel, shafts and caverns – is growing and requiring more specialist additional resources.

Finally, the design work for the test and reception facility of LHC superconducting cables, started in 1997, came to an end with the successful commissioning of the facility.

Mechanical Calculations and Measurements

Stress and displacement measurements at cryogenic temperatures for the LHC superconducting dipole magnet models and prototypes was again the main measurement activity supported by the Group and mechanical measurements on the three prototype LHC cryogenic lines were completed. Vibration measurements and analyses on a full-scale test segment of an experimental LHC vacuum chamber were continued for the LHC-VAC group with a view to optimizing the layout of supports and using novel vibration damping materials.

Mechanical and thermal calculations for the LHC machine and experiments, carried out mostly with the help of specialists from external collaborating institutes, included structural analyses of experimental vacuum chambers and the LHC quadrupole magnet beam screen, a continuation of the study of the fast cool-down of LHC dipole magnets in test conditions, as well as an analysis of thermal deformation of the dipole magnet cryostats. Structural analysis support continued for LHC detectors (CMS, ALICE) and to a lesser extent for the CNGS project (fatigue analysis of the magnetic horn).

Robotics and Heavy Handling

The work of the ESI-RH section, in charge of robotics and handling activities, was last year concentrated on studies and procurement of special transport vehicles for test and installation of LHC magnets.

The work to define and provide gantry vehicles to handle LHC cryomagnets and cold masses around the assembly and test area continued in 2000 with the management of the vehicle design and construction contract adjudicated in November 1999. Following successful factory tests in December 2000, the first vehicle will be delivered early in 2001. A solution for unloading and transporting cryomagnets and cold masses between test and storage areas and the SMI2 LHC tunnel access shaft was also defined, in collaboration with the LHC and ST Divisions, based upon the use of a mobile crane and road transport trailers. Engineering feasibility studies for transport and installation of arc cryomagnets in the LHC tunnel were completed. A specification for the necessary vehicles and unloading equipment was produced, and following a call for tender the contract was adjudicated at the December Finance Committee. Work was started on 3D simulation of vehicle operation in the LHC tunnels and liaison galleries to allow co-ordination of transport space requirements and design work for the installation of LHC infrastructure and services.

Studies were made to demonstrate the feasibility of precise transfer tables to install LHC ring cryomagnets in the tunnel and findings from these studies were used in the magnet interconnection design work. This work will continue with preparation of a specification and call for tender in 2001.

Engineering Support and Technologies Division 299 Remote-handling activities were limited to one radioactive area intervention to carry out maintenance work in the Antiproton Decelerator complex using the section’s service vehicle.

Engineering Support for Machines

In addition to the design and mechanical construction drawings related to the LHC machine, the ESM group is becoming more and more involved in the preparation of the SPS accelerator for the LHC project. The ESM activities continued to benefit from six designers detached to CERN by the Russian IHEP laboratory and had conversion work for beam transfer lines carried out at the BINP laboratory in Novosibirsk.

Magnet Cryostats

The cryostat section of ESM offers support to the LHC-CRI group which is in charge of the integration of the equipment of the LHC machine. In 2000 a major effort went into the definition and design of the cryogenic Distribution Feed Box (DFB) in close collaboration with Novosibirsk. A substantial number of design months were also dedicated to the cryogenic module (QQS) which links the magnet cryostat to the cryogenic line. This delicate equipment involves sophisticated vacuum and cryogenic hardware, and the work requires all the impressive capabilities of the EUCLID software. In addition, the section worked on the cryostat of the main dipole and its supporting system, as well as the cryostat of the arc quadrupoles. Prototype ‘cold feet’ in glass fibre material, similar to the ones developed for the prototype dipoles, were provided for the pre-series dipoles and were delivered in 2000 to the LHC-CRI group. A call for tender for the series production was also issued.

Together with the LHC integration group, studies on cryostats for the dispersion suppressor regions were started, and a new prototype full cell (String 2) is being studied. Finally, the ‘capillary’ tubes, which must carry an ever-increasing number of cables, are the subject of intense study in this section.

Magnet Connections

The LHC connection section works with the LHC-CRI, LHC-VAC and LHC-MTA groups studying all the interconnections between the main magnets of the LHC. This cylindrical volume of 1 m diameter and 1 m length is full of stainless steel pipes, superconducting cables, bellows, etc. All the equipment must be aligned and welded in situ, the execution time being a very important parameter. A special effort was put into the redesign of the main busbars, in collaboration with Novosibirsk, who will provide fabrication drawings.

The very sophisticated beam screen protecting the cold bore from synchrotron radiation was studied and optimized by this section. In the second half of 2000, a big effort was made to complete the more than 500 detailed fabrication drawings needed for the construction of the pre-series dipoles and the call for tender for the series production.

300 Engineering Support and Technologies Division Insertion Magnets

The insertion magnets section works mainly with the LHC-ICP group responsible for the insertion regions of the LHC. There is a wide variety of special magnets needed requiring thousands of hours of study. In some cases these studies are made in collaboration with US teams and, for the standard corrector magnets, with staff from the Indian institute CAT. In 2000, a special effort was made to produce the drawings for these correctors, with a team of six designers.

Model Work for LHC Magnets

This section, previously dedicated to the study of short magnet models, was mainly involved in the design of equipment for the magnetic measurement of dipoles at ambient temperatures, and the design of high-power diodes for quench protection. Nonetheless, the construction and testing of short (1 m long) dipole models continued in 2000 and still required a substantial amount of special tooling for assembly and for the measurement of the mechanical performance of the coils.

Work for SL Division

The ESM-SL section is in charge of all design work for the modification of the SPS machine to become the injector for the LHC. Among the many important contributions to the LHC project are transfer tunnels, injection systems, warm magnets, radio frequency cavities, beam observation monitors, and fast extraction equipment and absorbers for the beam dumping system. EST personnel assist the SL project engineers in questions concerning the manufacture of entire magnet systems or in some cases act as project engineers.

Studies for the transformation of the SPS machine progressed well and some important components will be installed during the 2000/2001 shutdown. A large number of shielding elements for beam impedance reduction were received and will be installed inside the pumping ports. The existing SPS inflector kicker magnet system had to be modified to achieve the required shorter rise time of 115 ns (−20%). This led to a redesign of the magnet and a reduction of the length of the individual magnet modules. Detailed design studies led to considerable savings in the overall cost of this transformation by the re-use of existing components. The pulse generators were also adapted to these new more demanding requirements. As the SPS cannot function without these elements, it was decided to install the modified magnet system in two stages during the winter shutdowns of 2001 and 2002.

The layout drawings concerning the SPS extraction system and the two transfer lines SPS-to-LHC were finalized and manufacture of several types of magnets has started. Design work on the LHC beam dumping system also progressed satisfactorily with market surveys for the magnet cores and the long ceramic beam pipe completed. The beam absorber systems as well as the radio-frequency couplers of the LHC cavities are progressing according to schedule.

Engineering Support and Technologies Division 301 Information Systems Support

The activities of the ISS group in 2000 concerned three main domains: Engineering and Equipment Data Management Service (EDMS), CAD support with extensive activities in 3D modelling and installation simulation for the LHC, as well as PC support for EST and AC.

The EDMS Project became the CERN EDMS Service at the beginning of 2000 with the ISS group responsible for all end-user support except in the electronics design domain. It should be noted that IT Division provides electronic design support as well as the computing platforms. During the spring a new, more feature-rich and considerably more stable Web interface was successfully introduced. The new interface also removed the old batch extraction system, giving online access to all data in EDMS.

The features now available in the EDMS service provide the tools for managing the complete life-cycle of any technical document including distributed approval processes and controlled distributed collaborative work environments using the World-Wide Web. The support for the management of other document types requiring life-cycles can also be envisaged on a larger scale. The CERN Drawing Directory (CDD) has provided a first- class service since its introduction in 1996. Its migration into EDMS is progressing well. The first phases, making the drawings visible simultaneously both in CDD and EDMS and giving access to the advanced CADIM/EDB configuration management features, are currently being tested.

The use of EDMS in the collider project and two of the experiments, ALICE and CMS, is extensive while ATLAS and LHCb have a less centralized approach. The LHC machine and CMS routinely use the approval procedures to introduce new technical documents and engineering change requests to manage design changes to their baselines. The challenge now being met is the management of data generated during the equipment manufacturing and test phases. The difficulty here is to provide a central solution with a wide variety of contracting industries given their disparate knowledge of computing in general and the Internet/Web in particular. The Manufacturing and Test Folder (MTF/Traveller) application is therefore being designed to be customizable to a certain extent. The MTF is based on Datastream Corporation’s MP5 which is already used by the LHC, SL and ST Divisions for equipment management. Access to the maintenance management environment of MP5 is via MTF which is now integrated into the EDMS framework. The role of equipment data management is of primordial importance to the projects themselves and will also help satisfy the requirements imposed by the French INB (Installation Nucléaire de Base) regulations.

The design of the MTF/Traveller has evolved and a more generalized approach has been taken which now starts to give good results for the production follow-up efforts for LHC corrector magnets. Work started in 1999 on the MTF/Traveller will continue throughout 2001. Support for the LHC equipment production and reception phases will require a large effort from the ISS group, both in terms of user problem analysis and application development. This work, done in collaboration with the LHC project management and the LHC equipment groups, is resource-consuming, but mandatory for the LHC Quality Assurance Plan and to comply with INB regulations.

Other divisions and groups at CERN, outside the activities directly related to the LHC project, have started to use EDMS to meet their own internal documentation management needs and obviously the EDMS Service itself uses the system to manage both its public and internal documentation.

302 Engineering Support and Technologies Division The LHC Division and the experiments have requested support for the management of both as-built structures and 3D model assemblies. A study project with CMS was launched and is expected to provide its first results during the spring of 2001. The complexity of managing structures is being understood and will require a careful analysis to define attainable objectives.

The LHC Digital Mock-Up (DMU) project is being carried out in collaboration with the EST Survey group, the EST design offices, and the LHC/CRI group and builds on the work already carried out on the tools and the procedures provided for the management of 3D models. The LHC project has launched a study on the integration of the large and complex LHC machine into the existing LEP tunnel. The LHC cryostats are much larger than the LEP magnets and the external cryogenic line makes the tunnel very crowded and many clashes, between installed equipment or with transport, must be solved in order to avoid unacceptable delays and extra costs during installation. Experience gained with LEP has already shown the help that Computer Aided Engineering tools could give to the integration effort. A virtual model of the whole LHC machine is being prepared and the actual LEP tunnel, which is known to good accuracy (centimetre level), has been modelled. All the elements of the machine are positioned accurately using data generated from the theoretical machine definition and the resulting layouts are used to generate reference sections and to check clearances.

More than 3000 users are now registered in EDMS. With an increasing number of users covering a wide spectrum of activities, the support load is steadily increasing; and it is not surprising that ideas for additional features develop rapidly with this increasing use. The central Helpdesk facility in the IT Division has taken over all problems peripheral to the EDMS and CAD domains and contributed much to keeping the support load manageable.

PC support in EST and AC is managed by the group in collaboration with the IT Division, taking advantage of their service contract. After some running-in problems, an acceptable level of service was achieved.

Logistics for LHC Experiments and Areas

At the end of 2000 the Logistics for LHC experiments and Experimental Areas group had 19 staff members and seven fellows and students. The group continues to have a collaboration with the radiation physics group of IHEP, Protvino within the framework of the Russian contribution to the LHC and last year a new agreement for the construction of part of the CMS radiation shielding structures was signed. Together the two agreements added about four man-years to the engineering capacity of the group.

The co-ordination work associated with the machine elements in the experimental areas such as the beam pipes and TAS absorbers continued and by the end of the year most elements were close to the final design stage. Only in the case of LHCb is there still an important amount of design and co-ordination work needed on the beam pipe for the vertex locator, where silicon detectors will be installed in a secondary vacuum separated from the beam vacuum by an aluminium foil only 250 µm thick.

Engineering Support and Technologies Division 303 Gas Distribution and Supply in All Experimental Areas

The Gas Distribution and Supply service (GDS) now maintains and operates about 55 km of gas lines, having taken over responsibility for the inflammable gases in SPS areas during the year. A new contract for the supply of liquid argon started in April 2000. The section distributes a total of 200 m3 of liquid argon a year at a cost of 200 kCHF, while other standard inert and flammable gases supplied in cylinders represent an additional ‘turnover’ of the order of 250 kCHF.

New gas distribution systems for the experiment COMPASS in the SPS North Area and HARP in the PS East Area were designed and installed and improvements in the GIF area in the West Hall are planned for 2001. To reduce the required manpower in the future, a remote monitoring system for the existing gas installations in the PS and SPS experimental areas has been developed and is being introduced gradually. The gas building 193 of the PS AD Hall has already been equipped and will be fully operational in 2001.

The new large gas installations for ATLAS and CMS were the subject of a market survey in spring 2000; and by the end of the year a draft technical specification was available ready for the call for tenders in spring 2001. Another call for tenders for a result-oriented operation and maintenance contract covering the totality of the detector gas distribution system is in preparation.

Support for ATLAS at Point 1

The AT section continued its general co-ordination role between the ATLAS experiment, the LHC machine, and the ST division concerning the infrastructure and general services at Point 1. A great deal of work went into the preparation of a call for tenders for the metallic structures needed in the access shafts, the service cavern, as well as the experimental cavern at Point 1. Because the metallic structures in the UX15 cavern also provide a general access and support structure to the detectors of the experiment, the ATLAS share of this call for tender amounts to some 40%. In 2000 the regular ATLAS experimental zone infrastructure co- ordination meetings made an important contribution to achieving the final designs not only of the metallic structures, but also in defining the radiation shielding along the forward beam-line needed for radiological purposes and background reduction in the ATLAS muon chambers. By the end of the year a technical specification was almost ready for the launching of a market survey for the part under the responsibility of EST-LEA. In addition, the section continued to be involved in the definition of the safety systems to be implemented for ATLAS and the layout of services, notably electronics racks and cabling and the design, supply and installation of detector gas systems.

Support for ALICE at Point 2

Work on the integration and installation of the ALICE detectors is progressing in parallel with the individual detector design and the development of the LHC accelerator. The layout of services is making good progress and the design of the radiation shielding has been adapted to the requirements of the magnetic compensation of the muon spectrometer magnet. In parallel with the dismantling of the L3 experiment, work has started on the modification of the SXL2 hall in order to prepare space for the assembly of the ALICE-TPC detector. A team from ALICE will be responsible for the removal of the central L3 support tube which will be

304 Engineering Support and Technologies Division cut into sections using a plasma cutter. The dismantling of existing safety and service installations has started with as much as possible of the recovered equipment being preserved for reuse.

The preparations to adapt the L3 magnet for the special needs of the ALICE experiment have been completed and technical specifications for the new structures and the repair of the cooling circuits are being prepared. About 50 t of iron will be added to each of the four ‘door-like’ magnet pole constructions and a protective moulding of resin will be applied to the outside of the cooling tubes to provide a long-term protection.

A single-layer, full-scale prototype winding for the Muon Dipole Magnet with reduced length and number of turns was successfully produced and tested in JINR Dubna while a mock-up of the magnet at 1:10 scale has been made in the CERN workshops. The wooden yoke corresponds to the manufacturing design concept and the coils are wound from solid aluminium conductor following the technology proposed by JINR. A call for tender for the excitation coils was launched in November.

Support for CMS at Point 5

The general co-ordination of the services and machine–experiment interfaces for CMS at Point 5 is progressing satisfactorily. The regular area working group (CEMESTE) treats all items from the beam pipe to the electrical distribution, cooling and ventilation, heavy handling, access and shielding and the safety monitoring equipment. Good progress is being made in the excavation of the underground structures at Point 5 and many of the surface buildings were completed in 2000 and are now being equipped with their general services. In the large SX5 hall the two 80 t cranes were delivered and installed, and the assembly of the CMS solenoid magnet has now started. LEA provides general support for construction of the magnet and detectors including co-ordination of the calibration and test beam areas.

The design of the experimental beam pipe at Point 5 is advancing well and now fully incorporates the requirements of the TOTEM detectors. The technical specification for the metallic structures in the access shafts, service caverns and experimental caverns have been completed and the call for tenders will be launched early in 2001. Cabling studies, including the necessary ducts and passages and associated radiation studies are almost complete for the areas and attention is now turning to the cabling of the CMS detector itself.

The LEA group is playing a leading role in the design and the co-ordination of three important radiation shielding elements for the experimental area. An agreement to supply one of these, the forward fixed shielding has been signed with IHEP, Protvino. Construction is scheduled to commence early in 2001 and the complete system will be delivered to CERN in spring 2003.

Support for LHCb at Point 8

The highlights of the contributions of the LHCb section in 2000 included contributions on logistics and safety to the RICH and Calorimeter TDRs submitted in September and a special study for the sharing of space in the protected area of the UX85 cavern to create a DELPHI museum. The Barrel of this LEP detector will be installed underground between the PZ shaft and the counting room structures being reused for LHCb.

Engineering Support and Technologies Division 305 A major effort went into the update of the EUCLID drawings of Point 8 in CDD, roughly 100 drawings are stored and an EDMS pilot project dedicated to the infrastructure and engineering issues is in progress. The adaptation of the existing infrastructure, logistics, and services at Point 8 will be clearly defined in a technical specification and will be used to update the installation schedule and budget estimates. Installation of the RICH1 detector and the Vertex Vacuum Tank were optimized using ROBCAD simulations.

In November, following the final LEP run, the dismantling of DELPHI was started with support from EST- LEA mainly aimed at a smooth transition from a DELPHI experimental area to one suitable for LHCb.

Support for TOTEM and Luminosity Measurements

The definition of the intricate interface between TOTEM and the LHC machine is proceeding well and the latest machine layout is fully compatible with detectors in ‘Roman pots’ some 150 m from the collision point. The powering of the inner triplet quadrupoles is also compatible with the special high-beta optics needed for the TOTEM measurements. An effective layout of detectors close to the collision point has been developed, compatible with both the machine and the CMS experiment.

Studies of a possible luminosity monitor based on a secondary emission chamber of the type used for many years at the PS, but adapted to cover the six orders of magnitude range in flux which will be needed for the LHC, have been completed and written up.

Manufacturing Facilities

During the year 2000, the MF group provided support to a growing CERN-wide user community, although the main activity of the group continues to be the manufacturing of components for the accelerators. In 2000 the MF group also had an increasing number of requests to act as subcontracting co-ordinator and provide technical know-how both to in-house and industrial partners.

This shift of CERN’s needs led in the course of 2000 to the decision to plan for spring 2001 a regrouping of all production activities and a reduction to only two structured workshops in Bldg. 100 on the Swiss site and Bldg. 904 on the French site. Thus making the surface of hall 112 available for other activities. The MF group will be reorganized in four sections for logistics, technical support, project co-ordination, and machine- tool maintenance.

During the year 2000 the MF group could count, in addition to some 52 staff members, on an efficient industrial support contract team with more than 80 collaborators. Two free-access workshops located in Bldgs. 109 and 904 are also provided for clients. The available exploitation budget in 2000 was at the level of 770 kCHF, and to cover the more than 7 MCHF cost of the industrial support resources, jobs in the workshops were charged to clients at a rate of 60 CHF/hour. The number of invoiced hours in the workshops totalled 126 000 hours in 2000. More than 49% of the total was for the LHC Division; the remainder was shared between SL (17%), PS (10%), EP (13%), and others (11%). Half of the production volume was machining (CNC and conventional), 20% consisted of more complex jobs combining several technologies and another

306 Engineering Support and Technologies Division 30% required metal sheet forming, welding technologies (TIG, MIG, Electron Beam and Laser) and other miscellaneous techniques.

Some of the most visible workshop productions during 2000 were:

– copper cavities, RF wave guides, couplers and antennas for various accelerators

– supporting structures and components for the LHC RF superconducting cavities

– a vacuum chamber and lead target for the nTOF facility including their installation

– a shuffling module and tooling for the DFB (Distribution Feed Box) of the LHC

– various types of LHC magnet laminations produced by spark-erosion

– a thin vacuum chamber for the NA48 experiment

– welding of LHC dipole magnets at Bldg. 181

– an extraction septum for the SPS

– RF cavities for the LIBO (linear accelerator) medical accelerator project.

Technical expertise was provided during 2000 for the following projects:

– cryostating and interconnections of LHC dipoles and quadrupoles

– manufacturing of the first octant of the big wheel supporting the ATLAS muons chambers

– technical specifications for welding, rolling and cutting equipment needed in the process of LHC cryostating

– technical follow-up of the CMS solenoid conductor production line

– logistics and quality follow-up for the production of muon chamber components for ATLAS

– logistics and quality follow-up for the production of the 7000 alignment targets for the LHC

– technical expertise and prototype manufacturing for the RF cell of the CTF3 project.

The subcontracting section managed projects for a total amount of 2.8 MCHF, mainly for the LHC, EP and PS divisions, but also for ATLAS and CMS. The subcontractors are shared among CERN’s Member States and four blanket contracts are in place with local Swiss and French companies to handle smaller urgent jobs. The subcontracting follow-up for the RICH components (vessel and composite windows as well as mirror supporting structure) of the COMPASS experiment was successfully concluded with the installation of the detector in EHN2. The quality control and metrology section was in demand for both internal and external quality assurance work, in particular for industrial supplies for ATLAS and LHC.

The maintenance section spent a total of 12 000 hours on corrective and preventive actions on the CERN machine tool park up to the end of September. At that time a new, lump-sum contract with the industrial partner came into operation. The activity is now under the full responsibility of the contractor. The special effort for the EU compliance programme continued in 2000, another 240 machine tools being upgraded,

Engineering Support and Technologies Division 307 bringing the number of EU-compliant machines up to 765. A further 200 machines will be upgraded during 2001 and the remaining 200 older machine tools scrapped.

Efforts were continued to keep the workshops up to date and the major investments in 2000 were:

– a mechanical retrofit of the Z axis of the FOREST large milling machine

– a new 2-axis rotating table for the FERRARI A16 CNC milling machine

– dedicated visualization programming software for the Danobat CNC lathe

– a retrofit of the THERMOZ spinning lathe

– a 3-axis, large-capacity CNC welding machine

– tube bending and folding machines

– a retrofit of the MECOF CNC milling machine in the workshop of Bldg. 100.

Surface and Materials Technologies

At the end of 2000 the SM Group could count on 42 staff, with one new recruit arriving and the departure of three retirees. The group provides a CERN-wide service, with assistance from industrial support contracts involving typically 26 persons. The additional project activities are mainly carried out by visiting staff (a steady flow of about 20, with the addition of about 10 industrial trainees). A brochure for potential clients describing the main activities and the equipment available in the group was published during the summer.

The rejuvenation project of the CERN large furnace for vacuum firing of machine components was successfully completed, although a precise evaluation of the vacuum performance improvement remains to be done. A call for tenders for the supply of a new vertical brazing furnace, replacing a similar facility dating from 1968 was launched and an adjudication proposal sent to the CERN Finance Committee.

In collaboration with the LHC-VAC group, a cleaning machine for the LHC dipole magnet cold bores was purchased, installed and commissioned. The machine was used for the cleaning of the LHC ‘String 2’ components with good results, following a procedure defined by means of samples analysed with Auger spectroscopy and electron stimulated desorption. The press purchased for the production of the ATLAS barrel baseboards was installed and is now ready for production. The chemical analysis capabilities of the group were improved by the purchase of a gas chromatograph equipped with mass spectrometry and a flame atomic absorption analyser.

Service Activities

All the SM sections continued to supply laboratory and workshop services to CERN-wide users. There was also a growing demand from other laboratories for thin film coatings, chemical treatments and vacuum firing, testifying to the competence and capabilities of the group in these fields. During the year 2000 work was carried out for CEA Saclay, PSI, Jefferson Lab., KFK Karlsruhe, INFN Legnaro, Sincrotrone Trieste and ESRF. A non-exhaustive description of the various service activities is given below.

308 Engineering Support and Technologies Division The Metallurgy and Brazing section was called on by the CMS experiment to help with components for their magnet in particular to help optimize the continuous extrusion process for the superconductor. Similarly the ATLAS experiment required metallurgical evaluations to satisfy TIS Division and the requirements of the experiment’s safety report, while for the LHC machine help was given for the preparation of several technical specifications for quality control requirements and for the characterization of materials and their assembly; notably for the beam screen, magnet cold masses and interconnection assemblies.

In the framework of the LIBO project, one of the most complicated pieces ever brazed under vacuum at CERN was a copper module which was assembled in 18 stages with 370 joints. With a weight of 340 kg and a height of 1320 mm it was also one of the largest. In addition, many development projects were completed during the year such as the assembly of carbon–carbon on nickel–copper and the use of new copper–beryllium alloys for the LHC interconnects and Invar for the cryogenic lines.

Last year the electrodeposition facilities of the Electrochemical and Surface Treatment section were fully used for numerous tasks such as copper plating inside an RFQ and the deposition of lead for a PS target. Cleaning of UHV components in the Prévessin facilities included notably the cleaning of 100 m of vacuum chamber contaminated by oil in an accident at NA48. The section was also called upon to prepare the cleaning of the cold bores of the LHC pre-series dipoles.

Analyses of gas mixtures and various plastic materials were made by the Chemistry and Polymer section for many experiments including CMS, ATLAS, COMPASS, ALICE and NA45. The section also made several other analyses for the LHC experiments such as resins for the impregnation of magnet coils. The production of the very special baseboards for the ATLAS inner tracker, where no outside manufacturer had been found, also started.

In the Surface Analysis section more than 200 analyses were made with the Auger spectrometer for the continuous monitoring of the CERN cleaning baths and also for the manufacturing control of various component suppliers to the LHC. The XPS analysis bench was improved with new acquisition software making the instrument more powerful and ‘user-friendly’. The number of measurements made with this instrument more than doubled with respect to previous years. Many collaborations were also established with outside Institutes, in particular where tasks required instruments which are not available at CERN.

The Printed Circuits and Photomechanical Techniques section answered numerous requests for the realization of ‘classical’ printed circuits as well as multilayer boards of up to as many as ten layers, some of particularly large dimensions. The success of GEM chambers continued with requests from many outside laboratories as well as CERN groups. A major production run for COMPASS has just started. The technology established for the production of GEM plates was also used to make prototype printed circuits of copper on polyimide.

The Thin Films section was busy throughout the year with, for example, coatings for the UV mirrors of COMPASS, very thin deposits of aluminium for temperature monitoring in the LHC, and metallic barriers to reduce the outgassing from plastic materials. Many deposits were made on cavities for the LHC and some for LEP2, when a new RF module was prepared in case of a last minute extension. As in the past, many ceramic components were routinely plated with titanium for the LHC, SPS, and PS accelerators.

Engineering Support and Technologies Division 309 The Analysis and Outgassing section carried out about 50 outgassing treatments of which about half were for the Swiss Paul Scherrer Institute. At CERN this activity reduced with the end of LEP. In the future improved performance of the oven and a better understanding of the diffusion and permeation of hydrogen in steels should allow further progress in lowering outgassing levels. Several studies of the outgassing of plastic materials were carried out at the request of the LHC experiments and were made using a new system following the relevant international norms. The evaluation of degreasing procedures for the cold bores of the LHC dipoles was completed by using electron stimulated desorption on test samples.

Projects

DESY Collaboration on RF Superconducting Cavities

The electropolishing equipment for TESLA niobium cavities, designed and operated by the group, allowed unprecedented accelerating fields of 40 MV/m to be reached in single-cell cavities. Following recent improvements the cavities are now treated under a controlled atmosphere. Basic studies on the H2 content and degassing of niobium were completed, showing that electropolishing does not result in increased H2 content and that effective outgassing may be made at temperatures lower than those routinely adopted. The performance improvement following in situ baking at 145°C was analysed and quantitatively correlated with the oxygen solubility and diffusivity in niobium. Remarkable progress was also achieved with niobium-coated copper cavities; their fields having been pushed to 28 MV/m. However, coated cavities continue to suffer an important ‘Q degradation’ above 15 MV/m, the origin of which is still obscure. The effect of H2 present in the niobium film, which is responsible for degraded RF performance in some cases, was thoroughly studied and quantified.

Non-Evaporable Getter (NEG) Coatings

The study of the vacuum properties of TiZrV getter coatings was continued by intercomparison of coatings on different substrates and by measuring the H2 dissociation pressure as a function of its content and film temperature. The study of the outgassing of rare gases at room temperature was completed, showing that less than 100 atoms of gas, trapped in the film during coating, are released per second and square centimetre after activation.

The systematic variation of the coating parameters has shown that film properties are very sensitive to the deposition rate and to the temperature of the substrate during coating, for both copper and stainless steel. When increasing the substrate temperature from 100°C to 300°C, the film morphology changes from smooth to rough, resulting in a 10-fold increase of surface capacity. By roughening the substrate prior to coating an additional improvement may be obtained, which renders the surface capacity of these films as good as that of commercially available getter strips. The ageing studies of TiZrV films, when submitted to repeated activation/air venting cycles, also continued both for coated stainless steel and aluminium chambers. In the case of aluminium, where temperatures cannot be higher than 180–200°C, 10 air ventings followed by a

180°C, 24 h bake-out result in a factor of eight decrease in the pumping speed for H2. In the case of the stainless steel chambers, which may be baked at higher temperatures, the H2 pumping speed reduction amounts to a factor of only three after 50 venting cycles followed by baking at 350°C for 24 h.

310 Engineering Support and Technologies Division The NEG coating technology has attracted the interest of other laboratories as well as of industry. Five undulator chambers were coated for the ESRF laboratory where they have provided a substantial reduction in the production of bremsstrahlung radiation, resulting in an annual three-week saving of machine time compared to uncoated aluminium or stainless steel chambers. More chambers will be coated for ESRF during 2001, and a similar request for two chambers has come from Elettra. Licensing to industry of the NEG film patent is under way with one firm having signed a contract, and others expected to follow.

CLIC

Since the autumn the SM group has been participating in the CLIC project, trying to help understand and cure the surface deterioration seen at high fields. It was decided to replace the copper, in the regions where it is damaged by cracks and craters, by more suitable materials (e.g. tungsten) either in bulk form or as a coating carried out by sputtering. An experimental set-up was designed to compare the behaviour of materials when submitted to sparking under vacuum conditions.

Positioning, Metrology and Surveying

The EST-SU group has a mandate to provide CERN-wide support for precision alignment and high- resolution metrology of components for accelerators and experimental equipment, and the maintenance of the Survey databases of all CERN sites through the Geographical Information System.

Geodesy

Last year a new survey monument was built and measured for the civil engineering works of the CNGS project. To ensure the best possible geodetic parameters between CERN and Gran Sasso, a joint study of the zero equipotential gravity surface ‘geoid’ with geodetic institutes in France (LAREG) and Switzerland (L+T) was completed. The final report shows an overall coherence between the various geoids studied, but displayed significant differences with respect to the geoid model used for LEP construction mainly due to improved source data in Switzerland. The integration of this data into a new geoid model is under way.

Calibration Facilities

The automated interferometric linear bench and the alignment calibration bench are both fully operational and were used extensively for various calibrations, technical evaluation of equipment, or reception tests of commercial instruments. A vertical calibration system was specially designed for digital levelling systems using Invar (encoded) staves.

Metrology of the Accelerators

The alignment of the SPS and LEP were maintained at a very high level, in order to be able to correct for the ground motion induced by the nearby civil engineering works of LHC and to provide the best possible

Engineering Support and Technologies Division 311 orbits for the last year of LEP. The alignment of the nTOF facility and the Antiproton Decelerator was also an important contribution.

The last possible measurements between LEP and the ground ‘Reference Network’ were completed before dismantling started. Specific statistical studies, using all LEP measurements, resulted in a more precise knowledge of the deformations and movements around the ring, and a number of studies on alignment tooling, tolerances and parameters were concluded. Metrological checks were also made on LHC prototype dipole magnets (curvature and assembly checks, cold mass stability, deformation of cryostats, etc.) and on the magnetic measurement benches themselves.

Within the R&D programme of CLIC, new adjustments and refinements were defined for the alignment systems of the 30 GHz CTF2 station. The installation of the new equipment has begun, as part of the pre- assembly for phase 2.

Metrology of Experiments

New critical detectors were installed and measured in COMPASS and HARP, and the PS and SPS experimental areas remained very active, with many LHC test beams being installed or modified. Numerous geometrical checks and tests, based on digital photogrammetry, were performed for the trial assembly of some LHC detectors on and off the CERN site (France, Germany, Japan, Portugal, Spain) at the request of the technical co-ordinators of experiments. The preparatory work for the design of the cavern reference networks and for the geometrical procedures to be carried out for the installation of the detectors also advanced satisfactorily.

Site Surveying and Local Affairs

The survey databases concerning buildings, pipe networks and geological data were completed, and the data regularly updated within the Geographical Information System (GIS). The new hardware configuration is now fully operational, various software developments were carried out and the Web package of the GIS will soon be accessible to other users.

312 Engineering Support and Technologies Division Finance Division

Introduction

Following the decision of the Council in December 1994 to approve the LHC project and the subsequent decision of December 1996 to build the machine in one phase under very stringent budgetary conditions, important civil-engineering work started in 1998. That work has progressed and important contracts, both for the machine and for the detectors, have been placed with industry. This implies very rigorous financial management as well as close control of the financial development of the project.

Within the overall policy during the construction period of the LHC decided by the Member States in 1996, the budget deficit of 41.17 MCHF for 2000 was approved by the Council in December 1999. It was mentioned in that document that cash would be available and in fact cash was sufficient on 31 December 2000. Therefore it did not prove necessary to borrow from banks during the year.

In 2000 important progress was made on the LHC project. Some 226 MCHF were spent on the machine and experimental areas (including some 78 MCHF for civil engineering). Furthermore, some 26 MCHF were spent for the four LHC detectors.

During the year, the Committee of Council decided to set up a Working Group to review the procedures on the payment of contributions of the Member States. The recommendations submitted by the Working Group are expected to be approved by the Council in June 2001 with a view to their coming into force with effect from 1 January 2002.

At the end of the year, new software for treasury and cash management was installed.

In addition, the Recruitment by Saved Leave (RSL) programme, introduced on a voluntary basis in 1998, was pursued in 2000 and made it possible to finance 38 Staff Member man-years.

As every year, two important items have been the preparation of the following year’s Budget and the Annual Accounts. In addition, there was the work associated with the audit of the 2000 Annual Accounts by the Spanish External Auditors with the corresponding reports to the Finance Committee and Council in preparation for the June meetings. A further important document this year was the one on the distribution by country of the LHC Project payments, outstanding commitments and adjudications from 1995 to March 2000.

Finance Division 313 Accounting Services

The recommendations of the External Auditors with regard to the presentation of special items, such as the residual value of cars, were implemented in the 2000 Annual Accounts.

Implementation of the Budget

Personnel expenditure amounted to 456.5 MCHF (425.1 MCHF for Staff Members and 31.4 MCHF for Fellows and Associates).

In 2000, the last year of the Recruitment by Saved Leave (RSL) programme, 1493 slices of 2.5% of basic salary were achieved on a voluntary basis, resulting in a sum of 4.1 MCHF. Thirty-eight Staff Member man- years (40 persons) have been financed through this programme. The unused appropriations have been credited to the designated reserve account, which amounted to 4.95 MCHF at the end of the year.

In addition to their regular contributions, two Member States made dedicated contributions to the LHC Project in 2000 (9.4 MCHF). Special contributions were also received for LEP 2000 (17.2 MCHF) and for the CNGS: 5.78 MCHF for 2000 and an advance of 6.02 MCHF for 2001.

Income and expenditure

The following is a summary of income and expenditure in 2000:

MCHF Income 1001.96 Contributions from Member States 930.86 Special Contribution from Switzerland to the LHC 8.60 Special Contribution from france to the LHC 0.83 Special Contributions from Member States and one non Member State for LEP 2000 17.19 From the Special Reserve Account for LEP 2000 10.00 Transfer from the LHC Reserve Account 8.08 Transfer from the AD Project 0.90 Bank interest 12.65 Unused reserves for accrued commitments 0.82 Special contributions for CNGS 5.78 Miscellaneous 1.90 Compensatory income 4.35

Expenditure 1029.00 Personnel 456.45 Materials 548.11 Debts 24.44

Allocation to Special Reserve Account 14.13 Budget Deficit −41.17

314 Finance Division 2000 S = 1 029.0 MCHF

Energy Debt repayment 5.3% 2.4%

Materials LHC project Personnel 22.0% 44.3%

Materials non- LHC project 26.0%

Fig. FIN–1: Total actual expenditure.

Invoices

The number of invoices handled in 2000 was about 46 000 and the number of related bank guarantees amounted to 390.

Cash Position

Timely payment of contributions by several Member States helped maintain a stable cash position during 2000. An important part of the liquid assets managed by the Organization relates to the funds of visiting research teams, collaborations and other third parties, as the level of payments related to the LHC project starts to increase. Interest rates for the Swiss franc and the Euro, better than expected in 2000, and a strong cash position, resulted in a higher income than foreseen of 12.7 MCHF.

At the end of the year, new software for treasury and cash management was installed.

Pension Fund

In accordance with the Council’s decision, since 1 January 1992 the Pension Fund has borne all its administrative operating expenses. In 2000 total actual expenditure (Personnel and Materials) amounted to 2.74 MCHF.

Visiting Research Teams

During the financial year 2000, there were 921 accounts open in our books for visiting research teams. About 6 100 invoices were made out for a total of some 35.6 MCHF. These monthly invoices relate mainly to

Finance Division 315 issues from stores, work done in the workshops or outside, orders sent to suppliers, and miscellaneous expenditure.

LHC Collaborations

The different accounts open for the LHC experiments (ATLAS, CMS, ALICE and LHCb) are now in full operation and regular reports are issued as necessary.

Following the various agreements CERN has concluded with its Host States, Russia, Japan, India, Canada and the USA, the relevant protocols and agreements relating thereto are in force. In order to handle the various operations, the corresponding open accounts enable the financial follow-up and the reports to be drawn up, as necessary.

During 2000 Finance Division presented the financial status of the ATLAS, CMS, ALICE and LHCb Common Funds and reported on financial matters at the relevant Resources Review Board meetings and on the LEP maintenance and operations accounts to the relevant Finance Review Committee.

Budget and Financial Planning

The Budget and Financial Planning Service prepared the Organization’s budget documents, the document on transfers and expenditure in excess of provisions, the cost-variation indices, the average inflation rates to be used in 2000 for the evaluation of price revision formulae and the scale of contributions together with the necessary background information for decisions by the Management. The service also contributed to the financial part of the Organization’s planning documents. It was particularly involved in the financial part of medium- and long-term manpower planning and in the Working Group on ‘Procedures for Payment of Member States’ contributions’. It also participated in the preparation of the Five-Yearly Review.

Computing, Statistics, and Financial Database

The Computing and Statistics Section is responsible for the divisional hardware and software support and for the provision of periodic reports like the six-monthly and annual reports on purchasing, statistics on the distribution of contracts and purchase orders by country for the LHC project, and ad hoc management statistics at various levels concerning financial and accounting activities.

316 Finance Division Debt repayment Energy 54 498 025.40 241.87 2 143.22 879 977.40 175 671.53 119 229.83 155 378.04 650 435.65 122 104.48 418 063.46 144 857.00 1 533 272.73 1 436 791.64 1 004 678.42 63 537 184.90 84 028 105.52 EST, ST, TIS ST, EST, 63 820.88 61 445.77 71 664.73 998 067.10 180 714.73 605 087.66 948 152.59 815 466.00 3 208 823.29 1 886 255.37 3 418 107.32 4 278 888.32 42 923 409.72 LHC, PS, SL 148 025 160.39 & Accelerator Accelerator & Direction Unit Direction Divisions 8 298.10 11 744.93 72 577.79 126 395.30 523 339.52 577 678.99 990 078.83 − 212 553.99 9 023 349.90 4 402 352.98 1 608 731.98 1 015 913.03 15 012 801.30 23 440 694.15 10 202 798.61 133 812 829.53 45.00 2 060.93 58 395.04 72 402.00 62 153.83 88 254.99 592 127.24 341 950.40 391 075.38 373 673.89 294 006.18 567 096.03 (in Swiss francs) 1 442 797.86 5 221 841.30 19 100 147.23 − AS, FI, HR, SPL TH ETT, EP, IT, Breakdown of 2000 Expenditure 2000 of Breakdown 90.68 8 032.50 65 724.54 22 329.70 104 851.47 811 435.51 756 309.04 232 330.79 448 218.73 339 991.75 871 569.87 General, 3 500 685.12 1 123 736.19 5 246 049.54 9 105 371.80 31 003 741.40 Directorate Directorate- Services Unit Services 8032.50 957 749.31 2000 2000 957 821.25 444 884.78 589 667.60 1 569 193.16 3 692 078.93 5 028 397.04 3 333 355.96 9 213 120.86 3 591 707.96 20 800 883.26 10 575 800.14 19 100 147.23 1 228 304.31 − 55 635 746.06 20 532 894.57 Expenditure 405 975 208.64 136 246 866.26 Breakdown Energy and fluids Energy premiums Insurance Library conferences seminars, Colloquia, services Industrial fees and payments party Third Consultants and Experts Public relations costs Training Duty travel expenses Official hospitality expenses Communications Recruitment Personnel activities subsidies offset to allocated Income expenditure Staff members Staff Fellows Associates Budget Personnel Centralized 2expenses Operating 239 891 434.2313 531 355.43 5 957 755.1142 940 367.60 54 365 549.16 68 598 381.5354 498 025.40 7 1 Personnel 456 452 039.27 9 105 371.80 50 768 417.87 157 848 980.73 153 1191 514.71 Personnel 85 609 754.16 616 621 622 623 626 628 671 641 2&3 Materials 548 109 665.08 14 719 398.10 7 959 398.47 95 894 090.57 212 509 277.79 162 529 474.75 54 498 025.40 6061 6184 6185 6226 6251 6252 6253 6491 6492 6493 TOTALS 1 028 998 377.35 23 824 769.90 58 727 816.34 253 743 071.30 365 628 792.50 248 139 228.91 54 498 025.40 24 436 673.00

Finance Division 317 Debt repayment 24 436 673.00 Energy 250 357.12 175 598.15 376 435.40 –830 750.00 –988 069.40 2 377 287.64 5 303 116.29 2 344 226.26 7 945 440.83 4 376 518.98 10 254 696.24 72 952 468.29 − EST, ST, TIS ST, EST, 923 457.11 715 611.46 112 637.05 370 842.34 –224 100.00 1 145 886.44 5 435 036.64 9 491 301.22 2 070 047.75 73 947 428.53 10 580 082.43 53 575 497.66 LHC, PS, SL & Accelerator Accelerator & Direction Unit Direction Divisions 19 674.50 207 792.84 58 922.19 325 308.06 –331 200.00 –897 913.85 3 385 730.85 4 836 209.30 9 826 182.49 3 743 829.92 2 985 528.27 3 812 529.13 24 981 129.27 322 206.76 69 102.10 50 246.39 20 958.57 328 951.77 683 185.75 526 992.02 (in Swiss francs) AS,FI, HR,SPL TH ETT, EP, IT, Breakdown of 2000 Expenditure 2000 of Breakdown 52 271.39 33 759.61 100 205.54 50 046.51 62 342.41 32 092.10 133 101.11 724 224.00 General, Directorate Directorate- Services Unit Services 207 792.84 2000 2000 –639 803.91 3 079 512.22 4 540 565.66 2 824 841.88 –1 386 050.00 87 945 954.69 73 124 027.53 15 610 286.08 18 938 438.18 74 069 797.50 18 806 021.20 11 096 846.98 Expenditure Breakdown Building and installations and Building equipment Industrial Data processing progress in Work stocks in Variations equipment Small Supplies cars of value Residual hire Equipment Maintenance research and Studies Transport Royaltiesfor patents, licences 3 Supplies 308 218 230.85 1 188 042.67 2 001 643.3652 953 722.97158 143 728.63 93 931 093.22 213 215 218 231 603 609 613 615 617 624 6063 6068 6511 Debt repaymentDebt 673.00 24 436

318 Finance Division Supplies, Procurement and Logistics Division

Introduction and Summary

In 2000, the procurement activities of the SPL Division further increased, with record numbers of market surveys, calls for tenders, adjudication proposals as well as important contracts and orders. Thus, 78 adjudication proposals were submitted to the Finance Committee, compared to 62 proposals in 1999. An additional workload for the Purchasing Service resulted from the fact that several contracts for the LHC project, which had been placed previously, required particular attention over the past 12 months. In some instances, companies met with considerable difficulties which made a change of contractor unavoidable. Examples are contracts for the supply of cryogenic feeder units for the test strings and the supply of superconducting wire for the LHC corrector magnets.

In parallel with the increasing procurement, the logistics activities of the SPL Division were significantly enhanced. The Shipping Service further strengthened its approach to organizing major transport itself, rather than relying on the suppliers. As in previous years, this approach generated important savings. The Service also solved customs and tax problems inherent in worldwide triangular traffic.

The group in charge of proposing and implementing CERN’s Industrial Services policy put its main emphasis on the evolution of manpower-oriented contracts towards task or result orientation where the companies take full responsibility for the work and for their employees. Considerable progress was made following studies conducted in several divisions in collaboration with SPL.

During the second part of the year, the SPL Division was involved in a number of discussions and negotiations with companies providing labour-intensive services on the site and being faced with the French law on the 35-hour working week and some new collective agreements in Switzerland. Acceptable solutions for both CERN and the companies have been found in all cases negotiated so far.

The Sales Service of the division made a major contribution to the LEP dismantling project. It prepared and successfully placed contracts with two companies for the sale and evacuation of large parts of the LEP machine and of the four LEP detectors. The service also organized the logistics for this operation.

In the framework of the planned reduction of CERN’s staff, the SPL Division will have to cope with a loss of some 18% of its personnel in the coming five years. This process has already started in the section which is in charge of the warehouse (stores), where three staff members left the section during the past year and two others are going to leave in 2001. As a consequence, the stores activities had to be entrusted to a service

Supplies, Procurement and Logistics Division 319 company which has been operating the warehouse since the beginning of 2000 and is now also in charge of the product management. This includes involvement in the definition of new stores items, preparation of technical specifications and participation in the procurement process.

Purchasing Service

The year 2000 was a particularly active year for the Purchasing Service, with no less than 78 Finance Committee proposals and as many as 81 market surveys and 126 calls for tenders. The number of orders for the whole of 2000 totalled about 38 880. This represents a further increase compared to the previous years.

For the LHC machine, almost all important contracts for building work, magnets and cryogenics have now been placed. Major contracts still to come concern the series production of the dipole cold masses, the assembly of cryomagnets on the CERN site, and the supply and installation of the cryogenic helium distribution line.

The alignment procedure was used in five cases in 2000. All requests for realignment of their tender prices to the lowest bids were accepted by the firms offering goods/services originating from poorly balanced Member States. The average difference between the initial quotation and the realigned prices was less than 5%.

As far as purchasing brokering is concerned, one of the companies engaged in that activity decided for financial reasons to stop its activities on the CERN site and a new company started on 8 May 2000. To date the latter company has handled about 1600 orders with an average value of 2000 Swiss francs.

The Purchasing Service also started a comprehensive web site, where all relevant information about purchasing can be found.

Logistics and Stores

Stores Service

The Stores Service provided goods to the CERN users for a value of some 18 MCHF in 2000. This is an increase of 9% compared to 1999.

The products offered by the Stores are continuously reviewed by technical working groups in which the product managers of the Stores Section closely collaborate with technical experts from the different divisions. During 2000 the review of fittings, valves and accessories, as well as heating and ventilation equipment and stationery was completed. The Logistics Advisory Committee approved the resulting recommendations which are now being implemented. The review activity led to an important upgrade of the product lines offered by the Stores and to improved standardization throughout the Organization.

320 Supplies, Procurement and Logistics Division The virtual store concept, whereby the goods are not stocked at CERN but are delivered directly from supplier stocks, represented 23% of the overall Stores purchase value in 2000. This concept has proved to meet CERN’s needs and will be further developed in the future.

Shipping and Reception Service

The number of shipments (import and export) and custom clearances handled by the Shipping and Reception Service increased from 39 000 in 1999 to approximately 42 300 shipments in the year 2000. The strongest increase was registered during the last three months of the year.

During 2000, the Shipping Service concentrated on organizing CERN’s worldwide shipments, mainly with the help of five best-in-class international logistics service providers. Special attention was paid to cost saving. To that end, the shipping service has extended its activities and now executes transport tasks which had previously been left to the suppliers or receivers.

The LHC project and the experiments involved CERN’s Shipping Service in various special shipping arrangements, for example the carriage of end-plug bodies for the ATLAS muon spectrometer between several European countries, the USA and Russia, or the transport of a substantial quantity of special steel from Japan to three European destinations.

During the second half of the year, there was an increasing requirement for transport of dangerous goods and radioactive loads. The repatriation of depleted uranium to the United States needed one year of preparation. This was one of the major radioactive shipping projects.

Certain administrative procedures within the Shipping Service (e.g. the shipping request) were reviewed. This has partly freed the personnel from their daily routine activities and enabled them to concentrate on important commercial tasks.

At the beginning of 2000, the French fiscal authorities imposed the payment of value added tax (VAT), with subsequent reimbursement, for all supplies of goods and services provided by French companies to CERN’s site in France. The Shipping Service, in collaboration with the Purchasing Service, has worked out procedures to avoid unnecessary costs and negative cashflows resulting from this decision. Advice concerning the customs operations and VAT has been systematically given to the users of the Shipping Service, often already at the tendering stage.

Industrial Services

The Industrial Services Unit continued, in close cooperation with the Purchasing Service, to work with all Divisions in drawing up market surveys and specifications for calls for tenders, and to handle an essential part of the administration and follow-up of service contracts.

Ten major industrial services contracts were placed in 2000. These included five retendered contracts, two new outsourcing initiatives and three contracts for the LEP dismantling.

Supplies, Procurement and Logistics Division 321 Besides that, the Unit was responsible for the co-ordination of CERN’s activities resulting from the new laws on working time in France (implementation of the 35-hour week) and some new collective agreements in Switzerland defining new minimum salaries. These new laws and regulations are applicable for CERN’s French and Swiss contractors, respectively, in the context of Industrial Services and, therefore, have a direct impact on the cost and performance of the contracts.

For the 35-hour law, solutions have been found and successfully negotiated with the companies. They will lead to more flexibility in the working time models for the service contracts concerned and enable the companies to provide their services in a way which meets the needs of the Divisions, while their employees will see the working time reduced to 1600 hours per year. There will be no additional charges to the estimated budgets for 2001.

With respect to the new collective agreements in Switzerland, some contracts had to be renegotiated with acceptable solutions for both partners.

The Unit played an active role in the definition and implementation of the new policy for temporary labour, which was agreed by the Directorate in 2000.

One of CERN’s main objectives regarding industrial services consists in the implementation of a more result-oriented approach where the companies take an increased responsibility for their employees and for the work. For this purpose, SL Division, PS Division, LHC Division and EP Division created task forces with the participation and active support of the Unit. The implementation of the results of this work has already started in two Divisions.

The Unit also participated in a discussion process with authorities, employers’ associations and unions from Switzerland concerning several topics linked to industrial services at CERN. The discussions were initiated and led by the Swiss authorities. They took place in a calm and constructive atmosphere and gave CERN a good opportunity to explain its position. These discussions will continue in 2001.

Storage, Recuperation & Sales Service

Recycling and Sales

The Recycling and Sales Service recuperates surplus equipment and scrap metal from various installations being dismantled at CERN and sells it to scrap-dealers in France and Switzerland. During the past year about 3000 tonnes of materials were recuperated and sold in this way. This corresponds to 460 truckloads being evacuated from CERN by various contractors. To achieve this, about 100 individual sales operations were carried through and it has generated an income for CERN of 865 000 CHF.

The Service also collects and receives various items which are obsolete but still functioning, such as furniture, small machines, desktop equipment, etc. and a direct sale of such items is organized on the site once a week. This has generated an income of about 70 000 CHF during 2000.

322 Supplies, Procurement and Logistics Division An online sales tool has been developed in collaboration with AS Division and installed on a new ‘Recuperation and Sales Service’ web-site.

LEP Dismantling

The Service has organized and is now handling the sale of all the material to be disposed of during the LEP dismantling project. Contracts with two companies have been placed for the sale and evacuation of about 20 000 tonnes of equipment and material.

In collaboration with the various divisions involved, the Service has also defined and organized the logistics for this operation. It has purchased and installed equipment and tools needed for the project, such as a weighing bridge, informatics tools, skips, etc. The Service has also taken care of the various administrative procedures involved.

The dismantling started in December 2000 and will last until spring 2002.

Storage

The SPL Storage Service mainly manages the storage space of Bldg. 133.

In order to free storage space for the LHC, a clean-up campaign was carried out to reduce the amount of equipment and materials stored by the divisions in this building. The campaign has initially reviewed all equipment stored for more than 10 years and this has led to a 35% reduction of all stored equipment. During the year some new additional equipment, representing about 10% of the total storage, was accepted for storage and a net reduction of 25% was thereby achieved.

During the year the Storage Service established a procedure and drew up a specimen contract for renting of storage space outside the CERN site.

Informatics Support Section

This Section guides and assists all SPL services in the use of computer software and hardware tools. It also helps users of applications relating to purchasing in all other divisions.

Computer software and hardware tools have continued to increase in quantity and complexity in the SPL Division. In order to respond to the ever-increasing demand for support and to face new tasks and objectives assigned to the section, part of the workload of supporting the SPL users has been assigned to contract staff, working on the basis of a service level agreement under the responsibility of the IT Division.

In collaboration with the AS Division and the AC unit, the section contributed significantly to the implementation of the Contract Follow-up (CFU) project, which is used systematically for market surveys, calls for tenders, contracts and the subsequent follow-up. The section gave CFU introductory courses to more than 100 users in various divisions and organized several information meetings for the Purchasing Service.

Supplies, Procurement and Logistics Division 323 The Delegate Information System (DELIS), which is used to transmit purchasing documents electronically to Finance Committee Delegates and ILOs, was further developed. It has been used to publish a sample of market surveys on the internet with a view to replacing the practice of dispatching the market surveys by mail. Work was started in collaboration with AS Division in order to integrate the functions available in DELIS into the CFU program.

The CERN Suppliers Database received some active maintenance, which included the suppression of several thousand companies which had not been contacted for years (the last clean-up was done about five years ago). Work went on, in collaboration with AS Division, in order to provide a better integration with CFU and to decentralize the use and maintenance of this database. A document is in preparation which describes how the database is handled.

In addition to the annual and six-monthly Reports on Purchasing presented to the Finance Committee, special information and statistics on purchasing were provided in the course of the year in response to specific requests from Delegates and ILOs. The total number of reports, lists and statistics provided adds up to more than 350.

Exhibitions and Official Visits of National Industries

In 2000 there were two national exhibitions, one organized by Poland (17–20 October) comprising 19 firms and one by the United Kingdom (14–17 November) comprising 30 firms.

Two national exhibitions and two visits of companies are planned for 2001:

– Belgium, visit of companies, 2–3 April,

– France, exhibition, 19–22 June,

– Hungary, visit of companies, 17–18 October,

– Germany, exhibition, 13–16 November.

324 Supplies, Procurement and Logistics Division Human Resources Division

Human Resources Policy Issues

Five-Yearly Review of Financial and Social Conditions

Every five years a review of financial and social conditions applicable to CERN’s personnel is conducted to ensure that these conditions remain in line with the situation in the Member States. In 2000, the Human Resources Division played a leading role in carrying out various studies, in particular the data collection enquiry in external comparison organizations and the private hi-tech sector in several Member States.

In December 2000, Council approved the package of agreements of the five-yearly review, recommended by the TREF Restricted Group, as a result of the foreseen conciliation process. These measures enter into force on 1 January 2001, subject to later implementation of some items. The main changes, which are described in more detail in the appropriate paragraphs below, concerned the following.

– Increase in the salary scale by 4.32% and in the scale of stipends of fellows by 1.52%.

– Redistribution of contributions to the Pension Fund, entailing an increase for staff and fellows from 9.37% to 10.12% and a reduction for the Organization from 21% to 20.25% of reference salary.

– Provision for the emerging issue of long-term care, within the CERN Health Insurance Scheme (CHIS). To achieve this, the contribution rate to CHIS was increased from 3.42% to 4.02% of basic salary and the contribution basis for beneficiaries of the Pension Fund was also increased.

– Introduction of a new career structure and advancement system, which aims to achieve better recognition and reward of merit. This is to be implemented in September 2001.

– Modification of the annual salary index formula, which better reflects developments in a wider sample of Member States, with the aim of ensuring closer adherence to this index between successive five- yearly reviews. Improvements and clarifications were also made to the methods and procedures of the five-yearly review itself.

– Introduction of an optional Saved Leave Scheme replacing the previous programme of Recruitment by Saved Leave.

Human Resources Division 325 New Career Structure – Major Milestone Achieved

The envisaged human resources policy to move to a more dynamic and less uniform career system was one of the priorities of the five-yearly review. Both in CERN and in the tripartite forum this sensitive subject was given the fullest attention. A major stage was reached in the final ‘package’ of agreements on a new salary grid and statutory texts to come into force on 1 September 2001. These will provide the basis for extensive internal discussions during 2001 on the practical implementation details of the new policy, the first year of full operation to be 2002.

Review of Manpower Resources

Following the announcement by the Director-General to the Finance Committee in November 1999 that the Management was conducting a review of competencies and critical skills, a paper was presented to the Finance Committee and Council in June 2000 (Review of Manpower Resources CERN/FC/4271). The paper was based on an analysis by all CERN Sectors in collaboration with the Human Resources Division and the Strategic Planning Unit.

The paper reviews the history of CERN manpower resources over the period 1981–2000 showing the progressive reduction from a peak of over 3500 staff in 1985 to 2735 at the end of 1999. Along with these reductions, resulting from budgetary constraints imposed by Council, there has been a substantial change in the distribution of staff by professional categories resulting from changes in technology and the outsourcing of many tasks previously carried out by CERN staff. During the period of LHC construction the staff numbers will continue to fall. The Long-Term Plan (LTP) of November 1996 foresaw a target figure of 2028 by the year 2006, i.e. 23% fewer staff than today.

As a result of the review carried out by the Sectors it can be concluded that these numbers will be barely sufficient to carry out the construction work. The review identified a number of activities, not foreseen in the LTP, which have enriched the non-LHC physics programme of the Laboratory, without modification of the overall level of human resources.

To respond to the major challenge of LHC construction and then commissioning and operating of the machine and detectors in a period of major loss of experienced staff by retirements (by 2006 at least 35% of the present long-term staff will have left), CERN must intensify its efforts to develop its human resources particularly by selective recruitment of the most appropriate staff, by training (‘on-the-job’ and through more formal programmes), and by internal mobility.

The Sectors have also reviewed the present state of outsourcing. For those areas of Laboratory activities that have been correctly outsourced, there is general satisfaction with the service provided; CERN has access in this way to specialized services to satisfy short-term needs, especially for the LHC Project.

The review identified three areas, mainly connected to R&D for future initiatives to sustain the vitality of the Laboratory, which require additional resources not foreseen in the LTP and the current Medium-Term Plan.

326 Human Resources Division Facts and Figures about Staff Members

Human Resources Report

The CERN Human Resources reports are issued every two years and are highly appreciated. These reports give general information on CERN’s aims, the organization of its operations and a wide range of human resources subjects. The next report is foreseen to be published by mid 2001. Meanwhile, an update of the most important figures and tables was published in 2000.

Evolution

In the course of the year 2000, 169 staff members left the Organization and 121 joined. The manpower strength at the end of the year was 2702.

Staff breakdown by sector at 31.12.2000 Directorate Accelerator Research Technical Administrative DG 8 AC 25 EP 548 EST 222 AS 59 DSU 43 LHC 308 ETT 62 ST 258 FI 42 PS 272 IT 185 TIS 141 HR 80 SL 361 TH 26 SPL 62 51 966 821 621 243

As foreseen in the long-term plan of the Organization, staff numbers will reach the level of about 2000 in the year 2006. This decrease will be achieved mainly by a foreseen increase in the number of retirements. This implies also that recruitment opportunities will be more limited than in recent years.

3500

3000

2500

2000

Technical staff 1500 Manual workers and crafts(wo)men Administrators & office staff 1000 Applied scientists & engineers Research physicists 500 Total man-year ceilings forecast (in full-time equivalents) 0

1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Staff by professional category over the past decade (number of staff on 31 December) and forecast for total man-year ceilings (in full-time equivalents) for the next 10 years.

Human Resources Division 327 Staff Recruitment and Mobility

The number of published staff vacancies increased from 142 in 1999 to 183 in 2000. The number of staff applicants declined by 16% compared to 1999. The declining trend in the number of applicants in recent years continued, as also observed in general on the European labour market; this despite intensified efforts and new measures of publicity (see also below under Fellows, Associates and Students Programmes).

The scarcity of qualified applicants from under-represented nationalities, notably for vacancies in technical fields, as well as an increased number of offers which were refused (17% compared to 10% in 1999), caused delays in recruitment actions and the necessity of holding several selection boards to fill one post. These difficulties had a negative effect on the number of recruits from some of the Member States.

The composition of 169 staff departures shows a similar profile as in previous years. They include 111 staff taking retirement and 26 resignations.

Assessment Procedure for Long-Term Staff Contracts

The overall recruitment policy, by which the majority of staff members are recruited at an early stage in their career on contracts of limited duration up to a total of six years, remained unchanged. A new procedure defined in 1999 became operational at the beginning of the year 2000 implying an enhanced assessment process for long-term appointments by CERN-wide boards to ensure that the selected candidates possess the necessary competencies to meet long-term requirements and that the statutory criteria are applied coherently across the Organization.

During their first year of operation, two inter-divisional boards were involved in the granting of 28 indefinite contracts and 35 appointments concerning staff holding limited-duration contracts recruited on long-term contracts.

328 Human Resources Division Nationality of Staff Members and Fellows recruited in 2000

Staff Members Fellows

Applications Candidates Applications Staff arrivals Selected received invited received

Austria 27 13 4 11 6 Belgium 121 84 5 10 Bulgaria 55 7 1 4 2 Czech Republic 33 7 6 1 Denmark 32 21 1 3 1 Finland 34 24 6 7 France 1067 221 40 50 9 Germany 118 100 10 67 21 Greece 32 17 3 19 2 Hungary 31 4 6 3 Italy 520 151 15 62 15 Netherlands 36 14 3 10 4 Norway 19 18 4 Poland 91 29 2 9 3 Portugal 50 24 1 12 1 Slovak Republic 30 7 4 1 Spain 292 98 5 70 16 Sweden 33 22 4 14 3 Switzerland 142 43 4 6 1 United Kingdom 232 127 13 39 7 Non-Member States 14 8 4 16 5

Total 3009 1049 121 429 101

Facts and Figures about Fellows, Associates and Students Programmes

The Fellows, Associates and Students (FAS) programmes have a strong scientific and technological component. They are intended for young postgraduates, engineers and technicians, shortly before or after graduation, as well as established scientists from all over the world. The programmes therefore promote science and technology transfer and provide unique research and training opportunities in a high-technology environment.

The number of applying and selected candidates in 2000 is comparable to that in 1999, except for a 28% decrease in the number of Paid Associates applications.

Special efforts were made to publicize the training and employment opportunities at CERN, especially in the technological disciplines. Several measures were taken, including increased participation at recruitment fairs, better use of career guides, the production and distribution of information brochures and posters, as well

Human Resources Division 329 as presence on commercial employment websites. During the year, there were also continuous updates of distribution lists for vacancy notices, improvements to the content and presentation of the website of the recruitment service and general advertisements in the press.

Applications and selections by programme in 2000

Programme Applied Selected Remarks

Fellows 429 101 Including 3 fellows selected under the CERN– Asia and Israel programmes and 4 funded by the European Union.

Technicals Students 216 110 Including 1 student partially funded by Sweden.

Doctoral Students 71 37 Including 6 students funded by Austria, 2 funded by the European Union and 1 partially funded by Sweden.

Summer Students 617 157 Including 10 students funded by the United States, 6 by Sweden, 3 by Denmark, 2 by Hungary and 1 by Norway.

Scientific Associates 150 85 Including 6 Non-Member State candidates who have been proposed for fellow contracts.

Corresponding Associates 22 21 Including 2 funded by Israel.

Other n/a 12 Engineers for a one-year training period, 8 funded by Spain, 4 funded by Portugal.

10 10 engineers and technicians for a two-year training period, funded by the Rhône-Alpes region.

The five-yearly report on the Fellows, Associates and Students programmes, covering the period 1995– 1999, was presented to the Scientific Policy Committee and the Finance Committee and approved by Council in December 2000.

The CERN Fellows, Associates and Students programmes were recognized to be a major asset for the scientific and technological communities, and for the future of CERN. In order to increase CERN’s competitivity in attracting the best candidates, the following proposals have been made:

– reinforce the Fellowship Programme,

– optimize the use of the Fellows and Associates budget,

– open the Doctoral and Technical Student programmes to a wider range of disciplines,

– and increase the size of the Summer Student programme.

330 Human Resources Division In addition, there is a proposal to create a Trainee programme, which will unify and expand the current special programmes that promote the training of young scientists and engineers. All proposals will be funded within the existing budget of the Organization.

Temporary Labour

The number of temporary labour personnel was stable during 2000 providing an average over the year of approximately 75 person-years. The current contracts with temporary labour providers will expire at the end of 2001. In preparation for a call for tenders, a market survey was sent out in December 2000 to temporary- labour firms in the Member States.

Training and Development

The main objective of training is to develop staff to face the scientific, technological and managerial challenges which lie ahead at CERN. Most training is delivered via the centrally organized training programmes for which there is a steadily growing demand. In 2000 the Joint Training Board (JTB), which advises the Director-General on training policy matters at CERN, was reconstituted and now has more direct involvement of CERN management. It has been evident for some time that the existing primarily bottom-up approach to individual staff training should be complemented by more top-down input, and this topic is being given priority by the new JTB.

The Training and Development Group is responsible for the delivery of the centrally organized training programmes, under the guidance of the JTB and in close collaboration with the Divisions, for whom the Divisional Training Officers play a crucial role.

The Management and Communication Programme has seen major developments in recent years with the active involvement of members of CERN management, including the introduction of a curriculum for supervisor training and seminars tailored to the development of young professional staff. In 2000 the existing programme was consolidated, and various new seminars on project management and other subjects were added. There was increasing demand for such training, and positive feedback from participants and their supervisors. The demand for team building activities continued to grow.

The demand for French and English language courses was consistently high, and the increased use of CERN-specific material to anchor language learning in the work environment met with an encouraging response. For the English courses, participants are evaluated systematically twice a year, and if they pass the test, they move to the next higher level. A similar procedure is being introduced for the French courses.

The Technical Training Programme offers courses and seminars in over 100 topics in electronics design, mechanical design, software and systems technologies, office software and administration. There were many new topics and a high demand. In addition, pilot studies on web-based training as a complement to formal courses gave encouraging results. The group collaborated in the preparation (and web archiving, see below) of mandatory training for the LEP dismantling project. More than 2000 people followed this training.

Human Resources Division 331 In agreement with TIS Division, elements of a centrally organized Safety Training Programme were put in place. Subject to clarification of various resource issues it is intended to develop this programme considerably in the future. The group produced a prototype basic safety training course for delivery via the Web.

The Academic Training Programme, which offers short lecture series in a wide range of topics in particle physics and applied science, continued to attract good audiences. For many years these lectures have been recorded on video, and some retransmitted to Finland (and other countries). Development of web-based archiving of these lectures (using a technique which originated in Michigan and was developed in collaboration with ATLAS and CERN) continued in 2000 – and has resulted in more than 250 lectures/ seminars being published from a variety of sources including the 2000 Summer Student Programme and the 2000/01 Academic Training Programme. The lecture package incorporates high-quality audio, visual support material and video of the lecturer compressed so that it is viewable world-wide with standard home PC hardware and web browsers.

The group continued to provide support for the High School Teachers Programme via the steering committee, provision of rooms and equipment, and active participation during the event.

The topics covered in the 2000 training programmes are listed in one of the annexes to the present report. Full information about the current programmes is given in the Training and Development pages on the World- Wide Web. Training information is also communicated via the DTOs, the Weekly Bulletin, and a Training Day.

Most training enrolments are now made directly from these Web pages which link into the Electronic Document Handling (EDH) System. The Core Training Administration package (which links training data with the databases for personnel, accounting and suppliers and permits interrogation via the standard administrative tools) is used for the administration of the central training programmes. Upgrades to improve its operation and to extend its use to cover training organized by the Divisions are still waiting to be implemented.

All apprentices who sat their final examinations in 2000 for the Certificat Fédéral de Capacité (CFC) were successful.

As agreed in 1999 with the Geneva authorities, the Union Industrielle Genevoise (UIG) took over the first- year training of technical apprentices as from summer 2000, together with the initial processing of applications. In consequence, at the end of 2000 the staffing support for the apprentice programme was reduced by one staff member. Final selection of apprentices and co-ordination of the work placements during the second, third and fourth years remain the responsibility of CERN. The arrangements for administrative apprentices continue unchanged.

Equal Opportunities

As in previous years, the work of the Equal Opportunities Programme may be divided into four main categories: awareness, recruitment and career development, work environment, and work–life balance.

332 Human Resources Division Awarenes In a continued effort to raise awareness of the principles and practice of Equal Opportunity employment, presentations were made to CERN’s Management Board, several Divisional meetings, the Staff Council, ACCU and TREF. In addition, an article on the activities of the Equal Opportunities Advisory Panel (EOAP) appeared in the CERN Weekly Bulletin.

Recruitment and Career Development Recruitment statistics show that women represented 23% of staff hired in 2000. Although this proportion was in line with the applicant pool and with recent years’ experience, it was noted that the proportion of female candidates invited to interviews was anomalously low. The positive trend of women representing one-fifth of all recruitment to limited duration contracts will be monitored over the next five years to ensure that these same gender proportions are maintained with regard to longer term hiring.

The advancement statistics for 2000 show that whereas the positive evolution in career path changes that appeared in recent years was maintained, the tendency of the hierarchy to favour exceptional performance awards over double steps for female staff was again confirmed.

In comparison to the previous year, women today hold a 2% higher proportion of management positions up to and including Group Leader position. However, they remain significantly under-represented at higher levels in the Organization.

Work Environment Following the publication of an Administrative Circular on the Principles and Procedures governing complaints of harassment, members of the EOAP carried out investigations into a certain number of cases of potential harassment, both sexual harassment and ‘mobbing’. All cases were resolved without the need for disciplinary action.

Work–Life Balance The EOAP made proposals to the Management in the area of Work–Life Balance that centred around requests to work from home (teleworking), the facilitating of spouse employment in the region, and the establishment of measures to address the child-minding needs of CERN personnel with pre- school children.

All three of these proposals were positively received by the Management who have committed themselves to making concrete efforts in these areas in the course of 2001.

Social Security

Pension Fund

One of the Fund’s noteworthy actions during 2000 was to select a second actuary for the next actuarial review and a company able to carry out a highly sophisticated assets–liabilities modelling study. In liaison with the company chosen, the next steps were a major review of the input and the supply of data for those purposes. The assets–liabilities modelling study is of great importance for the future of the Pension Fund. It should lead to a better allocation of funds to different kinds of investment, and to a risk analysis that bears not

Human Resources Division 333 on one single investment category, but on the Fund’s assets as a whole. This will help in achieving improved asset management efficiency.

In the real-estate sphere, in the course of the year the Fund made two major purchases in the centre of Paris, based on very good yield criteria.

It continued to track investment managers and monitor their performances. In March, in the light of results achieved, it proceeded to reduce the amounts managed in the field of quoted small and mid capitalizations. During the autumn it wound up its dealings with its US small and mid capitalizations manager and replaced it by a different firm. It also appointed a new manager specializing in US equities.

Internally, the Fund examined the cost of the progressive retirement programme (PRP) and issued a favourable opinion with regard to its continuation, given the fact that at present it is cost neutral for the Fund.

The Governing Board held seven meetings in 2000, and it dealt with matters ranging as widely as approval of the draft annual report, an examination of the Fund’s website, indexation of pensions, the administrative organization of the Fund and selection of a new US equity manager.

The Fund Administration provided the necessary support for considering these subjects and more regular topics. It also ensured implementation of decisions taken. Similarly it provided all the back-up necessary to the proper functioning of the Investment Committee, which met seven times, and of the Moveable Assets and Real Estate Investment Committees.

In addition to these specific tasks, naturally the Fund’s Administration also kept the accounts for all its different assets, ensured the application of the Rules and Regulations, made pensions disbursements whose overall amount is growing constantly, and met a very large number of requests for information from members and beneficiaries. It also collaborated closely with the external auditors examining its accounts and management.

The Fund’s Annual Report contains detailed information on the subjects raised in this report of activities and many other issues.

CERN Health Insurance Scheme

The new contract with UNIQA (previously AUSTRIA Collegialität) started on 1 January 2000 following re-tendering in 1999.

In 2000 the internal rules governing the CERN Health Insurance Scheme (CHIS) were updated to be in line with the new contract. The rules came into force from 1 September 2000 and were distributed to all members.

The CHIS Board, a sub-committee of the Standing Concertation Committee, met monthly to review all aspects of the Scheme with particular attention given to containment of costs. The CHIS Board publishes a periodic newsletter called the CHIS Bulletin which is distributed to all members.

334 Human Resources Division Long-Term Care

Following the presentation of the first proposals on Long-Term Care (LTC) by the Management to TREF in September 1999, and presentation of additional information to TREF in November 1999, a third paper was presented to TREF in March 2000 which gave an executive summary of the Long-Term Care issue and the Management proposals to contain costs arising from the predicted increase of dependency cases among beneficiaries in the CERN Health Insurance Scheme. The paper also contained first ideas on the possible sharing of costs by the Organization and the beneficiaries.

Proposals to introduce a LTC scheme into the existing CHIS was part of the package of measures approved by Council in the framework of the five-yearly review. Detailed regulations will come into force as from July 2001.

Voluntary Programmes

The Organization continued to operate three voluntary programmes in the year 2000: Recruitment financed by Saved Leave (RSL), the Progressive Retirement Programme (PRP), and a scheme of part-time work as a pre-retirement measure.

RSL was introduced in 1998 to sustain recruitment at a time of unforeseen budgetary difficulties. It has contributed to maintaining the recruitment of young staff when a major change of generation of the staff is taking place. Financial participation of the staff in 2000 has remained at the level of about 1500 slices of saved leave that have provided the funding for 40 additional vacancies. As indicated above, this programme will be replaced, in 2001, by an optional Saved Leave Scheme which allows participants to purchase leave that can be taken at a later date or in the form of part-time work.

PRP, implemented in mid-1997, aims to facilitate progressive retirement and contribute to rejuvenating the staff age distribution whilst retaining the know-how and expertise of experienced staff on a part-time basis (50%). By the end of 2000, about 380 staff had been interviewed, of whom 135 had signed to participate in the programme. This represents some 60 man-years’ participation over the full year, meeting the Organization’s planning provisions. After a conclusive three-year trial period the programme was extended in April 2000.

Finally, the scheme for part-time work as a pre-retirement measure (usually 80% working hours), which was introduced in 1994, catered for about 50 individual situations in 2000.

These three schemes have now a significant impact on the Organization’s personnel budget, whilst attenuating difficulties in the transmission of know-how to younger staff.

Human Resources Division 335 About the Division

New Structure

The reorganization of the Division was completed in 2000 with the creation of five groups and the appointment of respective Group Leaders, one of whom came by internal transfer from another Division, and a second was recruited externally from the CERN user community.

Legal Work

The two Legal Advisers (one full-time and one part-time) were involved in various activities performed within the Division. In particular by participating in the five-yearly review process, which required the drafting of new provisions for the Staff Rules and Regulations (review of financial conditions and the new career structure) and by providing legal advice within various working groups and committees (notably SCC and TREF).

They also both participated in the drafting and finalizing of the new CERN Health Insurance Scheme Rules, which were adopted in September 2000. Seven administrative circulars were also reviewed and republished during the year.

While the rate of litigation and disciplinary cases was again relatively low in 2000, HR Legal Advisers had to face an increase of requests for advice by individuals concerning their personal situation, mainly for taxes and accidents/illnesses.

Some important work was also performed in the context of the Equal Opportunities Advisory Panel, in particular to handle complaints concerning harassment, as well as for various training activities.

Application of Social and Statutory Conditions

During the year 2000, the Social and Statutory Conditions Group organized the renewal of Swiss legitimation cards and introduced a new leave management system. The group also contributed to different projects related to social affairs.

Legitimation Cards

In the framework of a general renewal of Swiss legitimation cards, more than 4200 requests have been processed. Such cards are not only provided to Members of the Personnel, but also to family members. The treatment of each request, including the management of provisional documents covering the holder during the period of issuing of a new card and the entry in the database of details about each card has led to an important increase in the workload.

336 Human Resources Division Leave

It has been decided to implement a new leave management system, whereby the leave is attributed on a monthly basis. The implementation, in close collaboration with AS Division, required a large information campaign and training of those in charge of the management of leave in the different divisions. Indeed, the management of four different types of leave on separate accounts is new for the users of the system. An important number of manual actions and corrections in the OracleHR database and EDH system had to be performed in a short period.

Despite the sensitivity of leave issues and a migration to a new computer system, the good collaboration between HR and AS led to a smooth running-in of this system.

Social Affairs

Type of individual request dealt with by the social Affairs Section

Family (relations with partners, divorce, separation, childhood, relations with adolescents) 28.30%

Health (coverage, invalidity, handicap, home care) 26.70%

Integration (residence and work permit for partners, new arrivals) 22.30%

General questions (income tax, legal advice, insurance, attestations) 12.60%

Work-related (relations at work, overload, demotivation, harassment) 5.60%

Financial (dealing with requests for reimbursement of debts) 4.50%

The Social Affairs Section also contributed to the following projects: nursery school, long-term care programme of preparation for retirement.

Volume of some of the administrative tasks performed by the Social and Statutory Conditions Group in 2000

Service Volume

Official travel (including on joining and leaving CERN) 7908 Education grants 2941 Installation indemnities 198 Home leave 1430 Removals 211 Reimbursement of invited candidates 455 Legitimation documents 8770 Formalities for new staff 191 Changes of family status 178 Other 645

Human Resources Division 337

Directorate Services Unit

The Directorate Services Unit (DSU) provides administrative and technical support to the Director- General and the Directors.

The Head of DSU co-ordinates various administrative actions common to the whole of the Unit, co- ordinates the staff advancement exercise, and represents the Unit at various levels in the Organization.

Office of the Director-General

DG Secretariat

The secretariat provided the Director-General with secretarial and logistics support.

In 2000, there were 39 meetings of the Directorate and 10 meetings of the Management Board. A number of meetings were also arranged between the Director-General, the Directors, and the Division Leaders to discuss various aspects of the management of the Organization.

Secretarial support was also given to the organization of the LEP Fest in October 2000.

Offices of the Directors

These offices provided secretarial and logistics support to the Directors. In the case of the Director of Administration, his office included other services which are described below.

Office of the Director of Administration

The office provides technical, administrative and secretarial support to the Director of Administration and manages the resources for the DG/ADM Sector. It also carries out the activities of administrative relations with the Host States and VIP visits.

Directorate Services Unit 339 Management of Human and Financial Resources

Activities carried out by the office on behalf of the Directorate and the Divisions in the Administration Sector (AS, DSU, FI, HR and SPL) include centralizing the requisite information for budgetary and human resource planning, drawing up annual investment and operating budgets, managing project requests for the Sector and subsequent budget implementation, and taking the necessary measures to contain the financial commitments within the fixed budgetary framework.

In collaboration with Human Resources Division and on behalf of the Administration Sector, the office centralizes recruitment requests, manages recruitment within the staff complements framework, and manages staff advancement and co-ordination of the annual performance appraisal exercise for DSU. The office also looks after various central budgets including communications (for which it provides, in close collaboration with the Organization’s technical services, administrative co-ordination with the postal and telecommunications authorities in the Host States), keeps abreast of developments in office automation techniques at CERN (BHT, EDH, Workflow Manager, HR, HRT, AVCL, CFU) and oversees their introduction in DSU.

Relations with the Host States

In the framework of relations with the Host States, the Administration continued to represent the Organization in contacts with the French and Swiss administrative authorities at all levels. More specifically, it dealt with the residence and employment of the spouses and children of members of the personnel, transit through the tunnel connecting the various parts of the site and across the border, arrangements with the customs authorities and police forces, measures to protect property and people, transport and traffic matters, the status of contractors and their personnel, and various administrative procedures.

VIP Service

The service receives the important guests of the Director-General as well as those of the Directors. The year 2000 has been very fruitful for the VIP Office with a record 135 visits for a total of 1037 visitors.

Relations with Member States

Information about the state of particle physics in the Member States as well as their activities at CERN was collected through contacts at CERN and visits abroad. A number of these visits were organized by Restricted ECFA on the occasions of its regular reviews of particle physics activities. Summaries on the status of particle physics in a number of Member States were written and published in the CERN Courier. Briefings were provided and meetings to solve specific issues were arranged.

Talks on particle physics and other CERN-related activities were presented at several schools and meetings, as well as at meetings organized by international organizations and foundations. Efforts to inform colleagues from other fields about particle physics were made through membership of Academies and of various important committees.

340 Directorate Services Unit Co-ordination of the CERN Schools was continued. Partial support for these Schools was obtained from UNESCO, the European Union and INTAS.

Relations with Non-Member States

The Non-Member States (NMS) service was conducted in 2000 with the help of advisors to the Director- General on relations with major NMS, with Eastern European countries, and with Latin America. As in 1999, there were two main facets to the work of this service in 2000. The first was meetings with senior visitors to CERN from many Non-Member State countries. In 2000 we received senior visitors from Canada, China, Georgia, India, Iran, Israel, Japan, Pakistan, Romania, Russia, Serbia-Montenegro, Thailand and the USA.

The second important part of the activity was in the form of visits to some of the NMS countries which were keen to enhance further their links with CERN. The Director-General visited Iran and Pakistan with a delegation from CERN, meeting senior government officials. Other countries which were visited in 2000 included the USA, Russia, Japan, Mexico, Armenia, Australia, Bolivia, Canada, China, Colombia, and Croatia.

There were discussions with several countries that may be interested in accession to full membership of CERN.

Other activities involved preparing Co-operation Agreements or Protocols to existing agreements which covered some of the countries cited above as well as dealing with the many visitors from less prosperous NMS who required financial help for their stays at CERN.

The leader of this service also took part in the CERN–Russia Committee and was Joint Chairman of the CERN–JINR (Dubna) Committee.

Council Secretariat

The Council Secretariat made the practical arrangements for two Council sessions, fifteen Committee meetings (Scientific Policy Committee, Finance Committee and Committee of Council), nine meetings of the Tripartite Employment Conditions Forum (TREF), eight meetings of ECFA (Plenary and Restricted). Furthermore, three Working Groups were set up by Council: i) on Majorities and Voting in the Finance Committee (three meetings); ii) on Procedures for Payment of Member States’ Contributions (three meetings); and iii) on the Enlargement of CERN’s Membership (two meetings); in all some 42 meetings.

The Secretariat co-ordinated the preparation and distribution of 542 documents (see breakdown below).

The office continued to provide the President of Council’s secretariat and gave secretarial support to the Chairmen of the Finance Committee, Scientific Policy Committee, and ECFA as well as to the different members of the Committees and the Chairmen of the Working Groups.

Directorate Services Unit 341 Document Statistics – Council Secretariat (2000)

Number of documents

Committee English French German Bilingual Total

Committee of Council and Council 53 53 3 7 116 Finance Committee 140 140 69 5 341 Scientific Policy Committee 15 4 – – 19 ECFA 20 – – – 20 TREF 38 – – – 38 Working Groups 8 – – – 8

274 197 72 12 542

Legal Service

The Legal Service executed its task as legal advisor to the Organization, to Council and its Committees and to the Directorate.

It worked on the preparation and conclusion of Co-operation Agreements with non-Member States.

It participated in three Working Groups set up by the Committee of Council and Council, on the questions of majorities, of CERN enlargement, and payment of the Member States’ contributions.

It also participated in the five-yearly review exercise and in its internal implementation.

The Legal Service continued the activities of the Working Group concerning the putting into place of guarantees in respect of pension payments in the event of the Organization’s dissolution.

It continued the dialogue with the French Authorities concerning the imposition of VAT in France and finalized this problem. It intensified the dialogue with the same Authorities on the fiscal status of the Organization’s personnel residing in France. It obtained from these Authorities the recognition of the international status regarding the investments of the Pension Fund in France and their fiscal exemption.

The Legal Service took an active part in the work relating to the territorial implantation of the LHC and the establishment of the ‘Convention sur les Installations Nucléaires de Base’ (‘INB’) which was signed on 11 July 2000.

It is involved in the matter concerning the request by the European Southern Observatory (ESO) to reduce the level of the latter’s contribution to the Pension Fund.

In the contractual domain, the Legal Service continued its activities as legal advisor to the SPL Division and other Divisions involved in the preparation and conclusion of CERN’s contracts. Considerable time was invested in contract work concerning the various civil engineering construction works, including now the

342 Directorate Services Unit neutrino project, and concerning the dipole magnets and other substantial LHC projects. It continued the revision of CERN’s General Conditions of Contracts.

The Legal Service pursued a number of patent applications and provided support to those involved in carrying out the Organization’s Technology Transfer policies. Substantial work is being done for the Datagrid Project and the Medipix 2 Collaboration.

The Legal Service continued its work in the field of insurance.

As far as litigation is concerned, the Legal Service defended the Organization’s interests at the Administrative Tribunal of the International Labour Organization (ILO) and at arbitration proceedings in connection with the LEP civil engineering construction works, and it continued the recovery of third-party debts to the Organization.

In the exercise of its duties, the Legal Service worked in close collaboration with the lawyers in other services at CERN, as well as with representatives of the Host States.

Internal Audit Service

The Internal Audit Service provides CERN Management with assurance that transactions are performed in accordance with approved regulations and procedures. It issues practical recommendations and advice to assist Management in achieving improvements where necessary. It reports directly to senior management and the Governing Board of the Organization’s Pension Fund where appropriate.

As in previous years, the Internal Audit Service was a point of control for tender openings, major purchase orders and contracts, new pensions and Pension Fund transfer values. Internal Audit also produced in-depth reports on purchasing, personnel, technical, and Pension Fund issues.

Internal Audit maintained a close working relationship with the members of the Spanish Court of Auditors who are the External Auditors to CERN and its Pension Fund. Internal Audit assisted them with the practical arrangements for their visits to CERN and acted as their main liaison point with the rest of the Organization. In the framework of this assistance, Internal Audit provided them special support for the audit of some particular areas. On completion of the annual audit cycle, Internal Audit followed up the External Auditors’ observations and recommendations, examining the areas concerned in greater depth where necessary.

In its role as an internal consultant, the Internal Audit Service was represented in working groups on the revision of CERN’s computing rules and the Monitoring Board on Purchasing Policy and Procedures. It also provided ad hoc advice on numerous issues during the year.

Strategic Planning Unit

The Strategic Planning Unit (SPU) continued providing support to the Management in corporate planning activities throughout the calendar year 2000. These activities comprised models development, strategic studies

Directorate Services Unit 343 and reports, and consolidated management information. In addition to its corporate planning responsibilities, it also co-ordinates the sectorial planning activities.

The primary output of the SPU activities in 2000 was the medium-term plan of CERN’s scientific activities and budgets estimates (CERN/SPC/779, CERN/FC/4270), which covers the years 2001–2004. SPU had both the development and editorial responsibilities for this document. In addition to the medium-term plan, SPU was also responsible for the edition of the annual LHC Project Status Report (CERN/CC/2354).

Closely linked to its primary mission, SPU carried out a number of quantitative studies. These studies focused essentially on the assessment of costs and simulations. In 2000, considerable effort was devoted to cost and funding scenarios in relation with the Five-Yearly Review.

SPU continued providing consolidated information for a number of economic and financial topics such as data and forecast on country-specific indicators.

More information on SPU activities can be found at: www.cern.ch/CERN/Divisions/DSU/spu/

344 Directorate Services Unit Administrative Support Division

Corporate Information Systems

The Corporate Information Systems group (AS-CIS) is responsible for the corporate administrative applications of the Laboratory. Our main objective is to provide CERN with a set of integrated and reliable corporate information systems. AS-CIS strongly supports the sharing of information with non-corporate or non-administrative applications to ensure coherent, reliable and accurate data.

The main applications under the responsibility of AS-CIS include accountancy, purchasing, contracts follow-up, inventory, materials management, logistics, human resources management, payroll, advances and claims, and various other smaller information systems.

These applications are used by over 1000 concurrent users (about 6200 registered).

Given the limited resources available, we aim at implementing, as much as possible, off-the-shelf solutions in a standardized environment with Unix/Oracle on the server side and the World Wide Web on the client side. We also aim to reduce in-house development to an absolute minimum. This strategy, compared to in-house- developed solutions enables us to:

– significantly reduce the development and maintenance effort;

– benefit from the evolution of software packages in functionality, technology and user interface;

– implement new requirements, wherever possible, using functionality that is already part of the package.

One requirement for the successful implementation of this strategy is that CERN users must adapt their working practices and procedures to the standard solution. With an extended functional coverage and diminishing resources, this has become essential.

A significant effort was spent to streamline, in collaboration with AS-DI-OP, the areas where administrative business processes or procedures add unnecessary complexity to our applications.

The leaves project, which was successfully completed in October 2000, has demonstrated this possibility to streamline procedures, by handling all leaves uniformly and thereby saving considerable manpower CERN wide. This major project also required the design and implementation of new payroll rules and slips.

The maintenance and support of applications in production occupies a large part of the available resources. This is the sum of pure support and the effort to keep our applications in line with the environment, excluding

Administrative Support Division 345 all new developments and overhead. As a result our users benefit from a very high service availability and total data reliability.

This work includes the follow-up of problems and bugs, communications with the suppliers, evaluation and deployment of new versions, specification of evolving requirements, and parametrization of the applications. A large effort is involved in user support, documentation and training. Statistics on the number of problems registered by the help desk per application area and time period are published on the Web.

In the area of stores and logistics, a lot of enhancements were implemented this year. Examples are:

– the ‘paperless’ exchange of information with suppliers (e-mail and fax are supported),

– enhanced traceability of cycle counting activity,

– functionality to support sales offers.

Following a smooth implementation and migration, the Electronics Pool is now using BAAN for the storage and maintenance of their equipment. All invoicing, which was a paper-based manual process, is completely automated and rental charges are now recharged on a monthly basis instead of twice a year.

It is our strategy to progressively move all Administrative Information Systems (AIS) applications onto the Web. The Web offers to end-users the advantages of a coherent environment, an intuitive interface and a thin client. For AS-CIS members, it brings the possibility to fully homogenize the client side of AIS applications, thereby reducing client side maintenance and costs. As can be seen from the items below, a very serious effort was invested in pushing this strategy forward.

In the Human Resources (HR) area, PIE (management of Persons Institutes and Experiments) was introduced and is now very successfully used by all LHC experiments. DELPHI, L3, NA48 are also using PIE and discussions are ongoing to get ISOLDE on board. PIE provides experiment secretariats with a Web-based tool to manage all information used by collaborations and experiments. This information is stored in the Oracle HR repository and a major effort has been devoted to merging sets of incoherent databases held at CERN to manage PIE information. For the first time at CERN, PIE provides a complete and coherent view of all data on persons, institutes and experiments and is the source data for the online publishing of the Grey Book on the Web. Initially based on an Applet technology, part of the PIE architecture has been re-designed using servlets in order to ease the implementation of additional modules for Personnel Administration in the Divisions (PAD).

The Personal Information Manager project, PIM, was also started within the HR area. PIM’s objective is to provide any person working at CERN with a Web-based tool to display all pertinent personal data kept on him/her, to let the person modify their own data whenever possible, and to guide the person through the CERN procedures. This tool will be based on a workflow system that potentially might be used as an electronic repository for CERN Rules and Regulations. The implementation of PIM, which will be the first introduction of CERN-wide self-help facilities, is ongoing.

Following the endorsement by the Council of the new career structure management, the HR team started work on its implementation in the HR and payroll systems.

346 Administrative Support Division AS-CIS evaluated Oracle*HR 11i, the latest ‘internet’ version of Oracle HR. After having envisaged all realistic alternatives for the IT support of the Human Resource Management business area, a proposed solution presented to HR Division on 21 January 2000 and later endorsed by the GTPA. Usability issues and costs have pushed us in the direction of a PIE-like solution for the divisional secretariats (PAD), while keeping the standard HR solution, with as few customizations as possible, for the sole use of central services like HR Division.

A major effort was devoted to the implementation of the Web-enabled version of ORIAC and SIRIAC, the accountancy and purchasing systems, in order to meet the deadline of October 2001. This includes the reception, testing, and installation of modules delivered by Inference as well as the migration of a large number of programs and reports to this new technology. AS-CIS takes the opportunity of this migration to streamline wherever possible the parametrization of SIRIAC/ORIAC and move closer to the standard product.

In close collaboration with the Finance Division, a new treasury management system was selected and purchased, Cash Flow Enterprise from DIAGRAM. Work is ongoing for the implementation of CFE and its interfaces to various systems.

A first study was performed to evaluate the various options we have to introduce a fixed-asset management system to replace our current ‘inventaire’ application, integrated with our finance and purchasing systems.

The Contracts Follow-Up project is nearing completion. It now covers the entire purchase procedures lifecycle as defined in the specifications. The CFU application was designed to manage and monitor the life cycle of contracts, purchase procedures, related documents, financial exploitation, analysis of planned and actual expenses etc. The requirements are defined in close collaboration with all ‘client services’. These services include SPL and FI Divisions, the Legal Services, Internal Audit as well as the DPOs from all sectors. Given the confidential nature of the data covered, special care was given to implement strict confidentiality rules. The CFU application interfaces with AIS applications: it feeds BHT with future expenditures, SIRIAC with contracts and amendments after their signature, and BAAN with contracts for the replenishment of the CERN Stores. Support for workflow was successfully introduced in October 2000 and allows the automatic routing and authorization of divisional requests. The implementation of a module for the support of cooperation agreements and the management of external funds is ongoing.

In the foundation area, all applications are now available on the Web. This includes new versions of the inventory application, GESLOC, GESCLE, courrier, and addressage.

A new sales of obsolete equipment application has also been made available on the Web. It has the potential to evolve into an online auction system, where anyone at CERN can suggest divisional equipment for sale. Auctioning is done over the Web, where anyone with an EDH login can make a bid. Non-registered users may also bid via email, or fax.

The Unique Supplier Database project is ongoing and will provide CERN with a single source of data for suppliers data, as well as a Web-enabled interface for the entry and maintenance of this data by the central purchasing services but also by third parties (ILOs, delegates etc.).

Administrative Support Division 347 The roles project, also started and on-going in the foundation area, will provide an extended unique data structure for the management of roles and assignments of roles to persons. This will offer a unique repository for all applications to handle security and access rights.

In an effort to provide AIS users with a single coherent interface to all AIS applications, on-line documentation and a wealth of AIS information, the Portal project has been set up and is progressing in the foundation team.

Smaller-scale projects were also successfully implemented during 2000:

The small-orders procedure now covers small orders up to 500 CHF. This procedure was designed to speed up the processing of small orders to go from the end user to the supplier in about 30 minutes. It has turned out to be a great success; close to 6000 small orders (an average of 400 orders per month) have been processed fully automatically since summer 1999.

The new CERN Classification Standard (CCS), an ambitious project which is a prerequisite for streamlining many processes at CERN, did not make as much progress as expected. However, we have a quality-assured and CERN-wide accepted classification structure since January 2001, and we are ready to start a gradual implementation.

Finally, in an effort to better advertise the AIS offerings to CERN, an AIS Newsletter has been designed and implemented and is published regularly.

In conclusion: 2000 has been used to set the grounds and prepare for the major migrations which have to take place before the end of the year 2001. Important projects are well under way, that should make a breakthrough in the way individuals and even third parties are led to maintain their own data. In the meantime, the availability and reliability of the information systems under our responsibility has remained close to 100%.

Internet Development Services

AS-IDS is responsible for the specification, planning, development, maintenance, and support of applications to enable end-users world-wide to initiate administrative actions, perform resource planning activities, or to obtain decision support information to assist in business processes. These applications currently include the Budget Holder’s Toolkit (BHT), the Human Resources Toolkit (HRT), the Electronic Document Handling application (EDH) and the Project Progress Tracking (PPT) application.

BHT

The BHT application allows budget follow-up for divisions, projects and teams. Since the beginning of 2000 the application runs exclusively from any web browser, enabling CERN budget follow-up to be performed anywhere once an internet connection has been established.

348 Administrative Support Division Owing to the re-organization in the division, responsibility for the application was taken over by a new Staff Member who successfully performed the 1999 annual book-closing, and who maintained the application improving many parts such as the application stability, the data extraction mechanism, the administration tools, and improved the technical documentation.

New functionality was also added to facilitate team accounting and for the electronics pool. The end-user documentation was completely revised and integrated onto the AIS website. The application ran throughout the year with no major problems despite the major resource changes, and over 1000 users continued to use BHT to assist them in their financial follow-up.

HRT

The HRT application allows human resource follow-up by section, group and division leaders, administrative staff, secretaries, and divisional administrative, planning and training officers.

Following the successful implementation of BHT on the Web, and the WebHRT prototype development which started in 1999 with the aim of making all ExcelHRT functionality fully available on the Web, 2000 saw a revision of the framework used for development of the prototype, followed by completion of the development. By the end of 2000 virtually all the Excel functionality was available in a test WebHRT version. The revision of the framework allowed re-use of many of the EDH development concepts meaning that knowledge-sharing and know-how were exploited within the group, which is important in times of shrinking resources. As for BHT, following the re-organization responsibility for the application was taken over by a different person, in this case an ex-member of the EDH team.

By the end of the year key Excel HRT users were testing and giving mainly very positive feedback on the WebHRT test version.

EDH

EDH is CERN’s internal e-business application with over 6000 active users connecting from 33 different countries and over 1000 different users a day using EDH to:

– Purchase any of the 16 000 standard stores items from the electronic stores catalogue.

– Make a purchase requisition which will be processed and transmitted to any of CERN’s 20 000 suppliers or any new supplier in the world.

– Request the import or export of goods.

– Request to follow an internal training course from the on-site training catalogue, or an external training course, conference or other event.

– Request vacation.

– Request overtime compensation.

– Request additional human resources for a project or activity.

Administrative Support Division 349 Over 100 000 documents are processed each year including the authorization process. This process ensures that the electronic document is sent to the correct persons for authorization depending on the type of request, and the rules such as financial or technical routing to which it must adhere; this process is known as workflow. Initially EDH had its own workflow application, however, during 2000 there was a gradual migration on a document-by-document basis to a commercial application and, in collaboration with the AS-OP unit, a dramatic simplification of the routing rules imposed.

Similarly to BHT and HRT, the re-organization had an impact on the resources assigned to the project which were reduced by around 50%. Despite this, and in line with the migration policy to full Web functionality, during 2000 it became possible to create more and more documents on the Web. Towards the end of the year the gradual running down of the ‘old’ client-server 2.1 version of EDH began. In addition to the increasing availability of documents on the Web, some new documents such as the IS37 (for disabling systems generating level 3 alarms) were added and all leave-associated documents were revised and the new personal schedule document was added as part of the new Leave Management System. An internal AIS collaboration resulted in the CFU application using the workflow functionality for routing of certain CFU documents, and integration between EDH and CFU for the generation of DAI documents.

PPT

The Project Progress Tracking system is a Web-based tool that allows users to enter up-to-date progress information for the tasks for which they are responsible via a standard web browser or via email. Project participants can view the status of the project from all over the world. All information regarding the project is stored in a central database which constitutes the foundation of the progress tracking system. The system also provides functionality for consolidation of project data and data analysis.

The initial ATLAS-specific development in 1999 included WorkPackage definition and expense tracking functionality. The year 2000 saw the merging of ATLAS and CMS’s needs into one unified PPT version with revised user and technical documentation and additional functionality including data maintenance tools, support for milestones, and an event notification system to inform users when management data has changed. Work also started on a Decision Support System.

During 2000 PPT functionality usage greatly increased: over 1500 new tasks were entered for future tracking. More than 100 task responsibles and project leaders created or signed off progress reports and a rapidly increasing number of users consulted the information.

Systems and Application Services

The SAS group, created early 2000, is responsible for the computing infrastructure of AS Division. It should provide a smooth and reliable service for the administrative applications supporting CERN’s business processes.

During the year the group provided support in four main areas: systems, databases, desktop and helpdesk.

350 Administrative Support Division Systems Area

During the year the group continued to provide system and operational support for the 23 UNIX servers running all CERN’s administrative applications. This included performing the necessary systems and database backups and recovery operations, user registrations, performance monitoring, capacity planning, installation of new machines, hardware and software upgrades. Support and administration of the Remedy request management system and of the Netscape web servers running in development or production was also offered. Electronic Data Interchange (EDI) services enabled electronic payments and interchange of data. A new and more reliable search engine for the AIS web site, and for our applications, was implemented. Tools for Change and Incident Management were developed. Web-based monitoring of Backups was also introduced.

Database Area

Support for operation, tuning and maintenance of the Oracle Database management systems was given. A total of 36 database instances were handled. As part of the standardization process the group concentrated on upgrading and migrating the databases from version 7.x to 8.x. Support on standard or common development tools to the different development teams was given. Oracle Developer and Designer were upgraded to version 6 on both UNIX and NT servers. We also provided assistance for the installation and migration of commercial administrative applications (HR-NCA, Qualiac, BAAN, etc). The evolution of the Internet led us to install new software for evaluation: Oracle iFS (Internet File System) and iAS (Internet Application Server). The tools used for performance monitoring and administration assistance were extended.

Desktop Support

We have continued to provide general Desktop support for Macintosh and PC users in the Administrative Sector.

Macintosh

A wide range of services were offered: hardware support, advice and purchasing, repair, maintenance, installations and configurations, advice on commonly used software, remote backups, remote software maintenance and distribution, file servers, shared agendas, etc. All new installations are based on a standard software model that contains a universal system package, standard applications and software tools. Additional specific software is installed on request.

The PC users were offered support on installations and configurations, handling of repairs, network connections, etc.

Administrative Support Division 351 AIS HelpDesk

The Helpdesk continued to record and solve requests for help with the AIS applications during the year. A total of around 4000 requests were recorded and the majority of them were solved within 24 hours.

Organization and Procedures

The Organization and Procedures Unit is responsible for the analysis, simplification, improvement and harmonization of administrative procedures currently in use by the Organization. In this context, the Unit inventories all inter-divisional administrative procedures in a handbook of administrative procedures. Particular attention is paid to obsolete administrative procedures as well as to administrative business functions currently performed using sub-optimal procedures.

The Organization and Procedures Unit also provides the secretariat for the ‘Comité de Liaison Administrative’ (CLA) which is composed of the Divisional Planning Officers (DPOs), the Division Leaders of the administrative divisions, and the Internal Audit, under the chairmanship of the Director of Administration. The CLA is a very important forum for discussion of procedural questions.

The maintenance of the handbook of administrative procedures is a recurrent and important activity which is performed in close collaboration between the O&P Unit and the ‘Groupe de Travail sur les Procédures Administratives’ (GTPA) which regroups representatives from all divisions. A member of the O&P Unit presides over the GTPA and reports to the CLA. The GTPA met seven times during the year 2000 with a very important participation of various CERN experts who were invited to discuss specific procedures.

In 2000, 81 procedures were examined and revised by the GTPA. These procedures were then approved by the Director of Administration via the CLA before they were published in the Web version of the handbook of administrative procedures.

A completely new leave and absence accounting system presenting drastic simplifications could be implemented on the planned date (1 October 2000), thanks to a close and continuous collaboration which took place between the implementing groups of AS Division (namely AS-CIS and AS-IDS), the O&P Unit helped by the GTPA, and the HR Division.

On the reorganization of the CERN organic structure (like CERN Sectors, Divisions and Groups), an important analysis work was carried out for documenting down to details of the optimal sequence of tasks to be performed.

As far as the CFU project (Contract Follow-Up) is concerned, two new important procedures (namely Adjudication and Contract) were completed and fully endorsed by the Co-ordination Committee. The new Contract procedure, which implements radical changes, is expected to save substantial time in the workflow of contract minutes.

On EDH (Electronic Document Handling), the CERN administrative workflow tool, a new electronic procedure dealing with security called ‘IS 37’ (Safety Instruction no. 37 for disabling alarms of level 3) was

352 Administrative Support Division successfully analysed and approved in close collaboration with TIS Division. This procedure was then implemented by the EDH team of AS-IDS. It should be noted that it was the first time that security considerations were considered rather than volume considerations for an implementation in the EDH context. Moreover, on the subject of security, the procedure for requesting and granting access to controlled areas to authorized personnel, was completely revised by the O&P Unit in view of replacing the use of a paper form by an EDH document directly linked to the AMS (Authorization Management System) application (operated by ST Division).

Finally, on streamlining administrative procedures, important simplifications could be achieved in close collaboration with the AS-CIS group and the HR Division by significantly reducing the number of different statuses (corresponding to the various categories of CERN personnel) used in the human resource application.

General Services

Mail Service

The new contract for outsourcing the sorting and distribution of mail was introduced on 1 June 2000.

Housing Service

The tender process was completed up to the adjudication of a new industrial support contract for the operation of the hostels, apartments, and ancillary premises run by the Housing Service. This single contract replaces the three previous separate contracts for the various activities involved as from 1 January 2001.

In view of the ever-worsening financial situation of the CERN-run apartments in France, the Housing Fund Committee had no viable alternative but to withdraw from this activity. In compensation, the assistance offered in finding rented accommodation on the open market would be reinforced.

Restaurants

A ‘Study of Feasibility’ was completed, as a first stage in implementing the recommendations of recent reports by various official authorities on the necessity to bring the kitchen and meal distribution facilities in Restaurant no. 1 into compliance with the legal hygiene and safety standards

A new free-flow distribution system was commissioned in the cafeteria of Restaurant no. 2. In addition to the typical items on sale in a cafeteria, the free-flow also includes all the articles previously available at the newspaper stand.

Administrative Support Division 353 Translation and Minutes Service

In 2000 the Translation and Minutes Service had to cope with a particularly heavy work-load of minute writing for 77 meetings. In addition to minutes for the usual sessions of the Council and meetings of the Finance Committee, the Committee of Council, and the Scientific Policy Committee, other records written included those for the Working Group on the Enlargement of CERN’s Membership (3 meetings) for Plenary ECFA (2 meetings), the Governing Board of the Pension Fund (7 meetings), TREF (6 meetings), and the Standing Concertation Committee (21 meetings). The work-load for the Standing Concertation Committee and TREF in particular increased substantially during the year as a result of the additional meetings in the framework of the five-yearly review of employment conditions. The Service was also responsible for drafting the summaries of the Management Board meetings (10) for publication in the Weekly Bulletin in addition to the minutes of those meetings.

On the translation side, work included the translation of 10 issues of the CERN Courier, Volume 1 of the Annual Report, and the official documents for the Council and its Committees, with an increasing number of adjudication documents for the Finance Committee. The Service also translated 107 technical specifications, 88 vacancy notices, the equivalent of 189 pages of Weekly Bulleting including the summaries of the Management Board, the Governing Board of the Pension Fund, and the Standing Concertation Committee, safety instructions, press releases and other CERN material.

Drafting assistance and linguistic editing of English originals continued to be an important activity for Finance Committee documents, in particular for adjudication proposals.

354 Administrative Support Division Technological Developments at CERN in 2000

Accelerator Technology Berkeley (US), IHEP, Protvino & JINR, Dubna (Russia), KEK, Subject: CERN radiofrequency Tsukuba (JP), Stockholm technologies University (SE), Technische Universität, Berlin (DE) Contact: E. Chiaveri/CERN–SL Contacts: J-P. Delahaye, G. Geschonke & A CERN R&D programme on reduced β nio- L. Rinolfi/CERN–PS bium/copper single superconducting cavities Within the framework of the world-wide started in 1996. The niobium sputtered on copper collaboration on linear colliders, the Compact technology has proved to be very successful with LEP2 up to the last day of functioning of the LInear Collider (CLIC) study explores the technical feasibility of beam acceleration by machine. Today a superconducting proton linac travelling wave structures at room temperature can be built to accelerate particles from 240 MeV to 2 GeV by transforming cavities developed for and high frequency (30 GHz) powered from a drive beam, the so-called Two-Beam LEP2 and having three sections β = 0.7, β =0.8 Acceleration scheme. CLIC covers a centre-of- and β = 1. Furthermore single-cell cavities reaching 40 MV/m have been obtained using the mass energy range for electron–positron collisions of 0.5–5 TeV. The CLIC study team is electropolishing treatment for the TESLA project. Two single cells have been produced for based in PS Division with the collaboration of SL Division, which has a specific mandate on the the SOLEIL project. Cavities have also been final focus and dumping rings. developed for the study of muon factories in collaboration with Cornell University. Twenty- Subject: Diaphragm system for preci- one superconducting cavities at 400 MHz are being produced for the LHC. These cavities are sion mechanical centring single cells, being built with the same technology Contact: A. Ijspeert/CERN–LHC successfully used for LEP cavities (copper on which a thin layer (1–2 µm) is deposited by The diaphragm system was developed at CERN magnetron sputtering). to cope with the requirement of assembling cylindrical superconducting coils inside a cylindrical tube with high centring precision, a Subject: CLIC strong holding force, and at a low cost. The Collaborators: INFN, Frascati (IT), LAL, Orsay, method consists of placing between the inner and CEA/CESTA, Le Barp (FR), outer cylinders a stack of flat washers of such a SLAC, LLNL, Livermore & LBL, shape that they can transmit a radial pressure

Technological Developments at CERN in 2000 355 from the outer cylinder to the inner cylinder. Subject: Power coupler with adjustable Since perfect circular washers cannot transmit a coupling factor for radial pressure, their shape is modified such that superconducting accelerator the nominal washer width is encountered only in cavities one radial direction over a reduced part of the azimuth, whereas over the rest of the radial Contacts: E. Haebel & H. Vogel /CERN– directions the width is reduced. Placing such EP, G. Roy/CERN–SL washers in different angular orientations around the inner cylinder will allow the transmission of An accelerator includes a beam tube having a forces from all azimuthal directions once the cavity with a central axis along which particles outer cylinder is placed over this assembly by a can be accelerated. A radiofrequency power- thermal or mechanical shrink-fitting procedure. coupling device couples the cavity to a high- The method secures also a precise centring. To frequency power source. The coupling device achieve this the washers need not be extremely includes a coaxial waveguide having a central precise, as long as they are all identical, which axis, an outer conductor and an inner conductor. can be obtained at reasonable cost by precision The outer conductor is fixed relative to the cavity punching. defining an angle between the central axis of the cavity and the central axis of the coaxial Patent: EP 0 399 123 PCT pending waveguide. An external drive moves the inner conductor along the central axis of the coaxial Subject: Magnetization measurements waveguide. on LHC superconducting strands Subject: Neutron-driven element transmuter Collaborators: Technical University of Vienna (AT), Institute of Physics of the Contacts: C. Rubbia & J.P. Revol/CERN– Polish Academy of Sciences (PL) EP, J.A. Rubio/CERN–ETT

Contact: L. Oberli/CERN–LHC A material is exposed to a neutron flux by distributing it in a neutron-diffusing medium Measurements were performed at T = 2 K and surrounding a neutron source. The diffusing T = 4.2 K in strands from seven different medium is transparent to neutrons and so manufac-turers with NbTi filament diameter arranged that neutron scattering substantially µ between 5 and 7 m. enhances the neutron flux to which the material is exposed. Such enhanced neutron exposure may Subject: Radiofrequency gun electron be used to produce useful radio-isotopes, in sources particular for medical applications, from the transmutation of readily available isotopes Collaborators: Paul Scherrer Institute (CH) included in the exposed material. It may also be used to efficiently transmute long-lived Contacts: P. Pearce & L. Rinolfi/CERN–PS radioactive wastes, such as those recovered from spent nuclear fuel. The use of heavy elements, Production of two 35 MW RF sources (one for such as lead and/or bismuth, as the diffusing PSI, one for CERN). Investigation of possible medium is particularly of interest, since it results performance limits for both thermionic and in a slowly decreasing scan through the neutron photocathode RF guns. energy spectrum, thereby permitting very

356 Technological Developments at CERN in 2000 efficient resonant neutron captures in the exposed hollow cathode hole. This feature allows the material. application of pseudo-spark discharge devices as powerful cold-cathode, high-current, high- Subject: Ferroelectric electron emission voltage switches.

Collaborators: Instituto Politecnico di Milano, Subject: Energy Amplifier University of Milano (IT), University of Katowice (PL), Contacts: C. Rubbia & J.-P. Revol/CERN– Thomson-CSF, Central Research EP, J.A. Rubio/CERN–ETT Lab, Orsay (FR) & Technical A method for producing energy from a nuclear University of Berlin, Inst. of fuel material contained in an enclosure, through a Theoretical Electrotechnics (DE) process of breeding of a fissile element from a β Contact: H. Riege/CERN–EP fertile element of the fuel material via a - precursor of the fissile element and fission of the Ferroelectric material is spontaneously fissile element. A high-energy particle beam is polarizing. The spontaneous electric polarization directed into the enclosure for interacting with field Ps of a ferroelectric layer is generally heavy nuclei contained in the enclosure so as to screened by charges on the surface. By a rapid produce high-energy spallation neutrons. The change of Ps apparent surface charge densities of neutrons thereby produced are multiplied in 2 the order of 1 Cb/m can be induced in certain steady sub-critical conditions by the breeding and ferroelectrics, high enough to generate electric fission process. The breeding and fission process surface fields and potential differences sufficient is carried out inside the enclosure. for pulsed electron (‘self’) emission without external extraction voltage. Hence, ferroelectric Subject: Phase space tomography electron emission differs from conventional Contact: S. Hancock/CERN–PS electron emission methods, which can yield a finite electron current only by means of an One of the simplest tomography algorithms has external extraction field. been modified to take into account the non- linearity of large-amplitude synchrotron motion. Subject: Pseudo-spark switches This permits the accurate reconstruction of the density in longitudinal phase space of particles in Collaborators: University of Erlangen (DE), a synchrotron from one-dimensional bunch Thomson-CSF, Central Research profile data. Lab. Orsay & Thomson-Short Systems, Bagneux (FR) Contact: H. Riege/CERN–EP Controls The pseudo-spark is a low-pressure gas discharge Subject: Four-quadrant power converter on the left branch of the Paschen breakdown curve. It occurs in a geometrical arrangement Collaborators: LEEI/ENSEEIHT, Toulouse (FR) with hollow electrodes, which are perforated with Contacts: G. Roy, F. Bordry & one or more axially symmetrical holes, through A. Dupaquier/CERN–SL which the main discharge plasma communicates with the interior of the hollow electrodes. The The LHC machine will make extensive use of pseudo-spark discharge can be efficiently true bipolar power converters which will be triggered with nanosecond precision from the installed underground leading to the necessity for

Technological Developments at CERN in 2000 357 reduced volume and high efficiency for the power measurement accuracy at currents greater than a converters. few kiloamperes, even in National Standards Laboratories, was at least an order of magnitude Subject: High-current, low-voltage lower. power converter

Collaborators: Danifysik A/S (DK) Cryogenics Contacts: G. Roy, F. Bordry, A. Dupaquier & G. Fernqvist/CERN–SL Subject: Cryogenic temperature measurement for large The LHC superconducting accelerator requires applications high currents (12.5 kA) and relatively low voltages (10 V) for its magnets. The converter is Collaborators: Helsinki University of made up using a modular concept where five Technology, Institute of Particle current sources (4 kA, 6 V) are placed in parallel. Physics Technology, RV- The 4 kA sources are configured in plug-in Elektroniikka oy Picowatt (FI) modules: a diode rectifier on the AC mains with a damped L-C passive filter, a zero voltage Contact: T. Niinikoski/CERN–EP switching inverter working at 20 kHz and an output stage (high frequency transformers, A resistance thermometry system has been Schottky rectifiers and output filters). developed for the acquisition, control and monitoring of temperature in large-scale cryogenic applications. The resistance of the Subject: High-accuracy current sensor is converted to a voltage using a self- calibrator balancing AC bridge circuit featuring square- Collaborators: Danifysik A/S (DK), Metron wave excitation currents down to 1 nA. The Designs (UK) system is easily scalable and includes intelligent features to treat special situations such as magnet Contacts: J.G. Pett, G. Fernqvist & quenches differently from normal operation. An B. Halvarsson/CERN–SL 8-channel prototype was successfully operated in the tests of superconducting microstrip line A very high precision programmable current detectors (RD39). A new version of the prototype ± source [ 5A] device with accuracy traceable to includes a card for diode thermometers, a card national standards has been developed. It is used optimized for 100Pt and rhodium iron sensors, as a key element in very-high-accuracy current and ADC resolution improvement to 20 bits. measurements. Overall resolution of the output current, stability and accuracy is at the 1 ppm Subject: Measurement of materials at 4.2 (part per million) level. The device can be used and 1.8 K either as a source or a sink of current. Using range extenders, like direct current–current Collaborators: University of Saragossa (ES) transformers (DCCTs), enables very high currents (up to 24 kA) to be measured to the Contact: N. Siegel/CERN–LHC 1 ppm level for the first time. In situ calibration, enhanced measurement accuracy, performance Measurement of material samples, including characterization and technical improvement of magnetic characteristics of steels, at liquid- DCCTs, now become possible. Previous helium temperature.

358 Technological Developments at CERN in 2000 Detectors The Gas Electron Multiplier (GEM) consists of a thin, metal-clad polymer foil, chemically pierced Subject: Mass production technology for by a high density of holes. On application of a

PbWO4 scintillation crystals difference of potential between the two electrodes, electrons released by radiation in the gas Collaborators: CEA Saclay, ISCTP & on one side of the structure drift into the holes, Laboratoire d’Annecy-le-Vieux multiply and transfer to a collection region. The de physique des particules, multiplier can be used as detector on its own, or LAPP (FR), IHE Bogorodysk, as a preamplifier in a multiple structure; in this IHE Minsk (Belarus), IHEP case, large overall gains can be reached in a harsh Protvino (RU), radiation environment. Contact: P. Lecoq/CERN–EP Patent: US6198798 PCT request

Full-scale investigation of solid-state characteris- Subject: Diamond tracking detectors tics of PbWO4 scintillation crystals for use in the CMS and ALICE electromagnetic calorimeters Collaborators: RD42 Collaboration and development of large-scale (over 50 000) Contact: P. Weilhammer/CERN–EP production technology using the Czochralski procedure. CVD diamond is a promising material to go beyond silicon in radiation hardness to build Subject: Further developments of hybrid tracking devices that survive many years of photodetectors highest luminosity running. The generated charge in diamond is 3600 electron-hole pairs per Collaborators: DEP (NL), EGETEC (FR), 100 µm compared with 10 600 electron-hole Preciosa (Czech Republic), RD7 pairs in Si. Samples are very reproducible and of Collaboration, RD19 good quality, not only in Charge Collection Collaboration, INFN Roma (IT), Distance (CCD), but also in leakage current, University of Rome III (IT) (non-polarization), spatial resolution and detailed Contact: E. Rosso/CERN–EP properties of the ‘Landau’ distribution.

A new class of photodetectors (hybrid photode- Subject: Microstrip detectors at tectors) has been developed which surpasses tra- cryogenic temperatures ditional photomultiplier performances. Their ano- des can contain from one silicon diode (hybrid Collaborators: RD39 Collaboration photomultiplier tubes) up to a few thousand silicon pixels with integrated electronics Contact: T. Niinikoski/CERN–EP (imaging silicon pixel array tubes). These Operating a heavily irradiated Si detector at detectors are single-photon and position-sensitive liquid nitrogen (LN2) temperature results in and have already been applied to count photons: significant recovery of Charge Collection to image particle tracks in scintillating fibre Efficiency (CCE). trackers, and to detect, by means of a suitable scintillator, γ- and β-rays over a wide range of Subject: Large-area advanced RICH energies. detector

Subject: Gas Electron Multiplier (GEM) Collaborators: RD26 Collaboration

Contact: F. Sauli/CERN–EP Contacts: G.Paic & F.Piuz/CERN–EP

Technological Developments at CERN in 2000 359 A large CsI Fast-RICH prototype of size Contact: P. Jarron/CERN–EP 1.3 × 0.9 m has been built which represents 2/3 of Study of the radiation tolerance of advanced a final module foreseen for the ALICE CMOS technologies and Commercial Off The experiment. Shelf (COTS) components that are expected to be placed in the radiation environment of the LHC Subject: High-resolution tracking experiments. devices based on capillaries filled with liquid scintillator Subject: Integrated time-to-digital Collaborators: RD46 Collaboration converter

Contacts: J. Panman & J.P Fabre/CERN– Collaborators: CAEN (IT) EP, G. Penso, INFN, Rome (IT) Contact: J. Christiansen/CERN–EP A large number of small-diameter scintillating fibres and highly integrated readout through A family of time-to-digital converters (TDC) for optoelectronic devices (e.g. 5 × 105 capillaries of drift time measurements with a resolution of 200– 20 µm inner diameter are read out by a single 250 ps r.m.s. image intensifier chain of 40 mm input window). Subject: Device and method to measure a short radiation pulse or an Electronics electric pulse Collaborators: CEA Saclay (FR) Subject: Timing, trigger and control (TTC) systems for LHC Contacts: G. Roy & E. Rossa/CERN–SL detectors A device for measuring a single short pulse Collaborators: RD12 Collaboration includes at least one measuring unit comprising a conductive line connected to a set of Contact: B.G. Taylor/CERN–EP photoconductors, the line and photoconductors At each of the CERN LHC experiments, timing, being placed between two nonconductors trigger and control (TTC) signals must be forming a single support in which the length of distributed to numerous electronic systems from a the line separating the photoconductors two-by- single location in the vicinity of the central two is equal to the product of the propagation trigger processor. A multichannel distribution speed on the line with respect to the duration of system has been developed which can broadcast the pulse concerning the number of measurement the signals to several thousand destinations from points, the lifetime of the majority carriers of the a few relatively high-power laser sources over a photoconductors being selected as being equal to passive optical fibre network with uncontrolled or less than 10% of the duration of the pulse. The path lengths. The multifunction optoelectronic device makes it possible to obtain a temporal TTC system shall meet the requirements of analysis or the autocorrelation of the pulse which central signal broadcasting and local distribution may be an electromagnetic radiation or ionizing in the various detectors. pulse or an electric pulse.

Subject: Radiation tolerance of Subject: Four-decade bandwidth hybrid integrated circuits coupler

Collaborators: RD49 Collaboration Contact: J. Belleman/CERN–PS

360 Technological Developments at CERN in 2000 This is a reciprocal radiofrequency building block business application. EDH currently has over with four ports. Signal power applied to any port 5000 active users with over 1000 different users a is equally divided between the two adjacent ports, day. An electronic document is processed every while the remaining port receives none. The 20 seconds. The system is multilingual, web- device has been developed to provide the sum based using a Java Servlet architecture, and runs and difference of the signals produced by an Oracle Workflow as the routing engine. electrostatic position pick-up in a particle accelerator. The ratio of difference over sum is Subject: LIGHT (Lifecycle Global directly proportional to the beam position within HyperText) the pick-up, and independent of the beam intensity. Contact: A. Aimar/CERN–IT LIGHT is a system that automatically represents Subject: Radiation-tolerant techniques and connects information, making it available as and circuits for electronic objects on the network. Receive information in systems any format and display information to any Java- enabled browser. Collaborators: RD 49 Collaboration LIGHT alpha 1.0 released 15.06.2000. Contact: P. Jarron/CERN–EP Subject: Automated beam steering and LEB–LHC R&D project dedicated to the shaping development of radiation-tolerant techniques and circuits for electronics systems at the CERN LHC Contacts: F. Di Maio, M. Lindroos, experiments. J. Schinzel/CERN–PS

The aim of the ABS Automated Beam Steering project is to give accelerator operators a set of Information Technology software tools to improve the quality of the beams they deliver. Subject: ART

Contact: P. Jönsson/CERN–AS Subject: CERN Document Server (CDS)

ART stands for Advanced Reporting Toolkit and Contact: J.-Y. Le Meur/CERN–ETT is a Java Servlet based tool for extraction of data SEARCH - permits one to search through the from a database using Structured Query bibliographic information and the full text of Language (SQL) and production of reports on the documents stored in CDS catalogues. Offers World-Wide Web. Reports can be represented in personal baskets, e-mail alerts. HTML in plain tabular form, pivot table form, as graphs, in XML etc. A large degree of flexibility SUBMIT - permits the electronic submission of is at the disposal of the report developer. documents from inside and outside of CERN.

CONVERT - offers a possibility to convert user- Subject: EDH uploaded documents from one format to another Contacts: D. Mathieson & J. Purvis/ (e.g. MS Word to PDF). CERN–AS SCAN - a possibility to have paper-based EDH (Electronic Document Handling) is the documents scanned. (CERN Intranet only, not three-letter acronym given to CERN’s internal E- free of charge.)

Technological Developments at CERN in 2000 361 AGENDA - offers a possibility to plan meetings Contacts: H. Muller & J. Bogaerts/CERN– or workshops and to store minutes. EP

SCI is a scalable industry standard (IEEE/ANSI Subject: TUOVI Standard 1596) for interconnecting computer Collaborators: CERN, Helsinki Institute of buses (PCI, VME, SBUS) via switch fabrics. It is Physics (FI) used in industry as interconnect for SMP desktop multiprocessors (Intel and Sun architectures) and Contact: H.-P. Hameri/CERN–EST achieves the highest bandwidth (4 Gbps) together with lowest latency (10 ms) of all current The TuoviWDM (Web Data/Document Manage- interconnect technologies. The application for ment) project aimed at improving disciplined and data acquisition in the Large Hadron Collider well-structured communication in distributed and (LHC) has been studied in collaboration with large-scale project environments. Dolphin by the RD24 Project since 1992, and concludes with an SCI demonstrator readout Subject: Data browser editor (VME, switches and desktop PCs) within the Contacts: J-M Bouche & G. Daems/CERN– ATLAS experiment. The RD24 developments PS include DAQ-specific PCI-SCI adapters for VME (PMC mezzanines), developed under CERN To provide the CERN PS Control system with a copyright. The robustness requirements of general tool which gives the possibility to physical SCI connections (optical fibres and maintain the operational values stored in the data copper links) have been studied for the LHC with tables of the software modules that control the respect to severe underground and radiation equipment. With this tool, one can edit, save, environments and have been submitted as ISO- store, compare the current operational data, the IEC Committee draft CD 14761. regularly saved values, and the so-called references. Subject: High-speed links and switches

Subject: HRT Collaborators: Netwiz (IT), Scali, University of Oslo (NO), SRF/PACT (UK), Contact: S. Foffano/CERN–AS University of Amsterdam (NL), University of Lubeck (DE) The Human Resources Toolkit (HRT) at CERN is a web-based decision support system used to Contact: R. Dobinson/CERN–EP view the current and past personnel situation (staffing, career, training, forecasts etc.). It CERN’s prime role in this project is to design and provides graphs, reports, drilldowns and OLAP build a large switching HS gigabaud network functionality. HRT is implemented using Java which will then be characterized with different Servlet architecture and the Advanced Reporting traffic patterns and loads corresponding to the Toolkit (ART) designed at CERN. needs of both industrial and LHC communities. Secondly, CERN will demonstrate the transmission of gigabit Ethernet traffic over this Subject: Applications of the Scalable Coherent Interface (SCI) in network which will both assist the take-up of the data acquisition technology at the industrial level and help to assess and characterize the cost/performance Collaborators: Dolphin Interconnect Solutions requirements of the ATLAS trigger architecture. AS (NO) CERN is also developing high-performance

362 Technological Developments at CERN in 2000 drivers to allow for the exploitation of the designed for high-energy physics experiments, available bandwidth. GEANT has today found applications outside this domain in the areas of medical and biological Subject: CRYOSIM - simulation sciences, radioprotection, and astronautics. The program for process calculation principal applications of GEANT in high-energy of helium refrigerators and physics are the tracking of particles through an liquefiers experimental set-up for simulation of detector response, and the graphical representation of the Collaborators: NTNU Trondheim (NO) set-up and of the particle trajectories. Contact: U. Wagner/CERN–LHC Subject: Object persistency Cryosim is a simulation program for steady-state process calculation of helium refrigerators and Collaborators: RD45 Collaboration liquefiers. The program represents a tool specially adapted to analyse the process of Contact: J. Shiers/CERN–IT existing installations under modified conditions. It can simulate from single components up to RD45 is a DRDC project to investigate object complete cycles, and may also be used for closer persistency for HEP. Persistent objects are those investigations of heat exchangers and expanders which continue to exist upon process termination in a specified process. Each component is and may then be accessed by other processes. modelled by writing its energy balance, the Transient objects are typically created by a equations are put into a unique matrix and solved. process and cease to exist when that process Since refrigeration cycles are mainly closed-loop terminates (or before). RD45 handles objects of processes, the program solves the complete all kinds: histograms, detector calibration and equation system simultaneously. geometry, production control. The main target is physics event data. Subject: Cooperating Expert Systems for Accelerator Control: CASE Subject: WIRED (World-Wide Web Contact: P. Skarek/CERN–PS Interactive Remote Event Display) To run the PS, some 10 000 control parameters need to be set correctly, many of them requiring Contacts: G. Kellner & M. Donszelmann/ updating every two seconds. In order to provide CERN–IT different types of beams for different physics needs, the control set-point values of many WIRED (World-Wide Web Interactive Remote accelerator components sometimes need to be Event Display) is a framework (written in Java) changed within a few milliseconds. to build HEP event displays that can be used across the network. WIRED has now grown to be Subject: GEANT4 - object-oriented a framework in use and under development in simulation software several experiments, both inside and outside CERN (CHORUS, ATLAS, BaBar and D0). It Collaborators: RD44 Collaboration has also proven to be useful to create event displays to explain high-energy physics to the Contact: R. Forty/CERN–EP general public. Both CERN (in the travelling The GEANT program describes the passage of exhibition and Microcosm) and RAL (during elementary particles through matter. Originally their open days) had such displays set up.

Technological Developments at CERN in 2000 363 Subject: ROXIE - A magnet design updated every year. A Mathematica-based software package computing platform for representation and manipulation of particle beam optics, for Contact: S. Russenschuck/CERN–LHC modelling of beam optics system behaviours, for Software tool for the optimization of accelerator specific beam optical or accelerator problems. magnets. Subject: NICE - Network Integrated Subject: RView - Java real-time Computing Environment graphical interface Contacts: D. Foster & A. Pace/CERN–IT

Contact: F. Momal/CERN–LHC The goal of NICE has been to create a single desktop environment from which users can RView (for Remote View) is a graphical interface access all the facilities of the laboratory. This in Java which graphically displays remote environment is currently based on Windows 95 variables which change in real-time. It was and Windows NT, where all applications are originally developed to remotely display and centrally supported, installed, and managed. interact with the status of industrial processes but it can be used for any kind of dynamic data. It is a full software environment which includes a Instrumentation & Surface window manager, a language interpreter, some network drivers, and a set of software Treatment components. Users can easily add their own Subject: The high-energy Reference components. Field (CERF) facility

Subject: CERN network security monitor Collaborators:

Contact: P. Moroni/CERN–IT – Austrian Research Centre Seibersdorf, Seibersdorf, AT Tool to analyse network traffic to detect suspi- – Atominstitute of the Austrian Universities, cious behaviour (intrusion detection). Vienna, AT – Royal Military College of Canada, Subject: ACCelerator Information Kingston, CA System - ACCIS – University of Prague, CZ – IPSN, Fontenay-aux-Roses, FR Contact: J. Schinzel/CERN–PS – Physikalisch-Technische Bundesanstalt, ACCIS (ACCessible Information System) is a Braunschweig, DE generic object-management system designed to – University of Kiel, DE allow data management systems to start small and – GSI, Darmstadt, DE to grow without software development. – GSF National Research Center for Environment and Health, Neuherberg, DE Subject: BeamOptics – University of Bremen, DE – University of Saarland, DE Contacts: B. Autin & P. Royer/CERN–PS – University of Siegen, DE BeamOptics is a Mathematica application which – ANPA, Rome, IT deals with basic charged particle optics in – Polytechnic of Milan, IT accelerators and storage rings. It is fully – INFN & University of Milan, IT documented in the report CERN 98–06. It is –INFN Frascati, IT

364 Technological Developments at CERN in 2000 – Tohoku University, Sendai, JP sequential distribution etc. This is a multipurpose – Institute of Atomic Energy, Swierk, PL adaptable device whose basic structure can be – CIEMAT, Madrid, ES used with a wide variety of tools. – The Swedish Radiation Protection Institute, Patent: FR 0004917 PCT pending Stockholm, SE – Dublin Institute of Advanced Studies, Subject: Electrochemical titanium Dublin, IR polishing – Institute of Naval Medicine, UK Contacts: C.Benvenuti & J. Guerin/CERN– – National Physical Laboratory Medical EST Division, UK – Civil Aviation Authority, UK Electrochemical polishing of titanium metallic – Department of Engineering Lancaster surface (either alloy or not-alloy) and description University, UK of the operating procedure. – National Radiological Protection Board, Patent: FR 9908151; WO2000FR0001694 Didcot, UK Subject : High-precision techniques for – NASA and Texas A&M University, Houston, ATLAS Tile Calorimeter US – Pacific Northwest National Laboratory, Collaborators: Joint Institute for Nuclear Washington State, US Research (JINR) Laboratory of Nuclear Problems 141980, Contact: M.Silari/CERN–TIS Dubna-Moscow Region (RU) A reference radiation facility providing particle Contact: M.Lyablin/CERN–EP composition and spectral fluences similar to those in the cosmic radiation field at commercial flight To develop, construct and test prototypes and a altitudes (10–20 km) is available in the North full-scale laser system for high-precision laser Experimental Area on the Prévessin (French) site control of the girder high-precision of CERN. This facility, in one of the secondary instrumentation, submodule assembly, module beam lines (H6) from the Super Proton assembly and the modules’ final dimensions for Synchrotron (SPS), provides a reference base for the ATLAS Hadron Tile Calorimeter detector. To testing, intercomparing and calibrating passive develop and prototype a system of fiducial marks and active instruments before their use on board to be placed on the calorimeter modules with high aircraft. precision. Also a mechanical system to be used to place reference marks in the ATLAS Subject: Interchangeable heads and experimental zone to allow continuous support device monitoring of the position of modules during assembly. Laser-based measurement system can Contact: J.C. Labbe/CERN–EP be used for control measurements of other The patented device allows the use of different different large-scale units. types of gripping tools for a variety of uses. The gripping head is made of a holding plate with Subject: Polycarbonate-based cryogenic suction cup and a punch. A contact measuring sealing nail at the end of the centre punch can measure Contact: P. Wertelaers/CERN–EP dimensions at the scale of one micron. A flowing liquid pneumatic syringe gun delivering a glue The possibilities and difficulties of realizing product with high accuracy in terms of quantity, cheap and robust cryogenic sealing, based upon a

Technological Developments at CERN in 2000 365 polycarbonate rectangular-section ring squeezed The CERN Laser Ion Source (CLIS) Project in between flanges with a ‘nose’ profile, have being developed by the Institute for Theoretical been examined. The properties and limitations of and Experimental Physics (ITEP) in Moscow will bis-phenol-A-polycarbonate are summarized and use a 100 J, 15 ns laser with a 1 Hz repetition compared with sealing requirements. rate. This source could be an option for the ion Computations of the flange’s nose indentation are source for the future LHC project. discussed. We derive from it estimations on cool- down shrinking problems, tightening forces, and Subject: Lasers: resonant ionization remaining elasticity. Flanged assemblies have been extensively tested in a liquid nitrogen Contact: G. Suberlucq/CERN–PS environment: shock quenches from room temperature as well as long-term exposures to the The aim is the selective production of ion beams liquid. Helium permeation through the seal has isobarically pure in terms of chemical elements. been measured as a function of temperature. A test in a liquid helium environment (4.2 K) has Subject: Lasers: photoemission been done. We further discuss experiences with the production of large-diameter seals, from Collaborators: CLIC Study Collaboration plastically deformed rods, butt-welded with a solving agent at one or more places on the Contact: G. Suberlucq/CERN–PS resulting ring’s circumference. Finally, we The aim is to produce very intense electron present first impressions on a promising, beams whose time and transverse profiles reflect alternative welding method. the incident laser beam. This is done by lighting a photocathode with a laser beam whose photon energy is higher than the photoemission threshold Lasers of the photocathode. At CERN, the photocathodes used for this application at the Subject: Laser ion study CLIC Test Facility (CTF-2) are made of cesium

telluride (Cs2Te) and have a photoemission Contacts: H. Haseroth & H. Kugler/ threshold of 3.5 eV. CERN–PS

With future requirements in mind, in particular for the LHC, the potential of laser ion sources for Magnets the production of highly charged ions is being studied in collaboration with two Russian Subject: Design and construction of institutes (ITEP and TRINITI). We are also 1.3 m long, 56 mm dipole model collaborating with the Czech Academy of magnet for a very high field Sciences which has a big iodine laser (capable of producing ultra-short pulses) and where Collaborators: Helsinki University of collaboration has started on different experiments Technology (FI), University of together with the Institute of Plasma Physics & Uppsala (SE) Laser Microfusion in Warsaw. Contact: D. Leroy/CERN–LHC Subject: Lasers: inverse Bremsstrahlung The design of a high-field superconducting dipole Contact: H. Kugler/CERN–PS model magnet for the LHC.

366 Technological Developments at CERN in 2000 Subject: Pseudo-spark switch wires with cross-sections from 0.38 × 0.73 mm to development for the LHC beam 0.73 × 1.25 mm is possible. The ribbon is in most dumping system cases strong enough to allow the winding of the tight bends in the coil ends without separation of Contact: G. Roy/CERN–SL the individual wires. Fast high-power switches (35 kV, 30 kA) are needed to pulse the LHC beam dump kicker Subject: Magnetization measurements of magnets. The kicker magnets extract the superconducting cables for the circulating beam in one revolution and dump it LHC on an external absorber. Collaborators: Slovak Academy of Sciences, Institute of Electrical Subject: Pseudo-spark switch Engineering (Slovak Republic) development for the SPS beam dumping system Contact: D. Leroy/CERN–LHC

Contact: G. Roy/CERN–SL The superconducting magnets of the LHC collider will require a large quantity of The SPS beam dumping system is equipped with superconducting cables. Magnetization hybrid high-power electronic gas switches, measurements on single strands are foreseen to composed of a thyratron, bypassed by three qualify the production of a new superconducting ignitrons in series. Ignitrons contain a large NbTi wire supplied by various European firms amount of mercury and will, in the foreseeable engaged in the R&D work for the LHC future, no longer be commercially available. It is superconducting cables. These magnetic planned to replace the ignitrons by an available measurements, required to control the three-stage pseudo-spark switch which has to be performances of the LHC wires, consist of adapted to the needs of the beam dumping measuring the magnetization hysteresis loop of system. single strands at 4.2 K and 2.0 K.

Subject: Manufacture and use of flat Subject: Field measuring probe for long superconducting cables magnets

Contact: A. Ijspeert/CERN–LHC Collaborators: Frauenhoher Institut fur Produktions Technologie, Technique to make coils for superconducting Aachen (DE) accelerator magnets by means of a ribbon (flat cable) consisting of a number of parallel Contact: P. Sievers/CERN–LHC superconducting wires. What is innovative is the Description of the technology used to carry out technique to preassemble insulated magnetic field measurements in a very controlled superconducting wires into a ribbon and the way along the narrow aperture of the up to 15 m technique to wind superconducting magnet coils long magnets. with such a ribbon in the form of a single or double pancake. A machine has been developed Subject: Superconductors for large to produce a ribbon from superconducting wires. magnets The ribbon dimensions are precise to within ± 0.01 mm. Fabrication of ribbons composed of Collaborators: Alsthom Belfort (FR), Brugg some 20 round wires of 0.38 mm diameter and Kabelwerke (DE), Cables de also of ribbons made from some nine rectangular Cortaillod (ES), CEA Saclay

Technological Developments at CERN in 2000 367 (FR), Rutherford Appleton Contact: A. Herve/CERN–EP Laboratory (UK), General Invest (Slovak Republic), SCSC (CH) & Common development of the electroslag welding University of Genoa (IT) method of thick (up to 60 cm) iron plates. CMS welding test development. Contacts: A. Herve & H. Ten Kate/CERN– EP Subject: Fluxless brazing of aluminium High-purity aluminium stabilized conductors Contact: P. Wertelaers/CERN–EP with performance well beyond present standards are required for the magnets of the ATLAS and In order to successfully braze aluminium alloy CMS experiments. For CMS, an additional assemblies without the use of oxide-removing mechanical reinforcement by an aluminium fluxes, an environment with very low jacket is needed. contaminant level is mandatory. This is mostly achieved by using a vacuum furnace. Brazing Subject: 15-metre-long ceramic coils for under inert gas of sufficient purity is also the field measurements of LHC possible. dipole magnet

Contact: P. Sievers/CERN–LHC

The use of rotating coils to measure the field Microelectronics quality over the whole LHC magnet. Subject: High-resolution pattern Upilex Subject: Quadrupole pick-up sheets

Contact: A. Jansson/CERN–PS Contacts: R. De Oliveira, A. Gandi, S. Neal & L. Mastrostefano/CERN–EST Quadrupole pick-ups measure not only the positions of the beam, but also the beam size, as it Working methods have been developed allowing does not intercept the beam. The ‘beam width’ the production of 70-micron wide metallization signal originates from the lowest-order non-linear patterns on large Upilex sheets under clean room term in the pick-up response. conditions.

Subject: Cryogenic monolithic Mechanical Engineering semiconductor detector

Subject: Automatic winding machine Contacts: W. Snoeys, L. Casagrande & V. Palmieri/CERN–EP Contact: A. Ijspeert/CERN–LHC A new type of ionizing radiation detector was The need to produce more than 25 000 super- developed, where a new device structure allows conducting coils for the corrector spool pieces of the integration of the readout circuitry and the the LHC has led to the investigation and then detecting element in the same piece of semi- development of fast and inexpensive coil winding conductor. Cooling at cryogenic temperatures methods and of a coil winding machine. allows increasing signal collection depth and the detection of charge generated deep in the bulk of Subject: Electroslag welding process low purity semiconductor material. Collaborators: TTS/ESAB AB (NO) Patent: WO 00103207 PCT pending

368 Technological Developments at CERN in 2000 Subject: Microelectronics and thermal LHC experiments will rely heavily on optical management links for data transfer in order to minimize the power and material budget at the front end and Contacts: A. A. Carter/CERN–EP, R. De allow transfer of data at high rates, while Oliveira & A. Gandi/CERN–EST remaining immune to electrical interference. The Thermal management systems can be fabricated very harsh environmental constraints in the heart using a wide range of pyrolytic graphites of the LHC detectors make the selection of incorporated into thin and low mass structures by electro-optical components suitable for use in encapsulation. Such structures can be made optical links very challenging. robust, are radiation-hard, and are safe to handle. They can be used as a substrate for fabrication of Subject: Radiation hardening of silicon electronic hybrids, where they can provide the detectors option of double-sided connectivity. Electronic Collaborators: RD48 Collaboration hybrids, fabricated separately, can also be directly interfaced to the thermal management systems, Contacts: M. Letheren & M. Moll/CERN– by fusing. The systems can be incorporated into EP composite structures in order to provide customized thermal sinks. The devices operate The engineering collaboration with silicon over a wide temperature range, and can support material and silicon detector manufacturers as the high-speed, densely populated systems as well as with solid-state institutes continued. Main used in today’s miniaturized electronics. The aims: processes of encapsulation, interfacing and the – Manufacturing of silicon monocrystalline new hybrid technologies are protected by materials with various concentrations of International Patent Application Number PCT/ atomic impurities, such as oxygen, carbon, GB99/02180 filed in the names of CERN and nitrogen, germanium, tin, etc. Queen Mary & Westfield College, London. – Processing of silicon detectors from these Patent: WO 00/03567 PCT pending materials – Microscopic characterization of the silicon Subject: Readout of calorimetric materials before and after irradiation detectors for LHC – Electrical characterization of silicon detectors before and after irradiation Collaborators: IMC, SICON (SE), RD16 Collaboration Subject: Radiation-hard Contacts: B. Lofstedt & R. Forty/CERN– microelectronics readout EP technology

A readout system for detectors requiring a very Collaborators: RD29 Collaboration large dynamic range (>16 bits) and high Contacts: R. Forty & P. Jarron/CERN–EP resolution (>12 bits). A mixed analog-digital radiation-hard technology Subject: Optical links for LHC detector for high-energy physics electronics. Evaluation of front-ends the radiation-hard DMILL 0.8 mm BiCMOS technology for applications in analog and mixed- Collaborators: CERN, Imperial College London mode detector readout circuits at the LHC. (UK), HEPHY Vienna (AT) Several prototype front-end chips for the ATLAS Contact: F. Vasey/CERN–EP silicon central tracker have been developed.

Technological Developments at CERN in 2000 369 Subject: Gas desorption studies Subject: Hood clamshell tool

Collaborators: LURE Orsay (FR) Contacts: A. Jacquemod & J.C. Brunet/ CERN–LHC Contact: O. Grobner/CERN–LHC Device to test leak-tightness of vacuum systems Collaboration to measure synchrotron-radiation- of different diameter pipe junctions based on induced gas desorption from vacuum chambers at hood methods. It consists of a single unit device, 4.2 K and 77 K. This experiment is installed on a part of which is leak tight and part of which is a dedicated synchrotron radiation beam line on the bearing structure, permitting detection of leaks at VEPP IIM storage ring. the limits of a detector’s sensitivity, in the present − case 10 10mbar.l.s –1 (standard limit of leak detector). Leak tightness tests are made from the Vacuum outside on components with circumferential welding and the system is especially suitable for Subject: Arrangement and method for areas of restricted access and where pipes are improving vacuum extremely long. Patent: FR9915814 PCT pending Contact: C. Benvenuti/CERN–EST

It has been shown that thin film coatings of Non- Evaporable Getter (NEG) materials, produced by Technology Transfer Through sputtering, may recover their chemical reactivity Special Projects by in situ baking at temperatures as low as 180°C thus transforming the vacuum chamber into a Research in particle physics and the development pump. of particle accelerators, detector systems and Patent: FR9702305 PCT pending application software by CERN, and others, has traditionally led to applications outside the Subject: High voltage vacuum insulators domain of particle physics, and in particular to applications in the medical field. Therefore, one Contacts: B. Goddard &G. Roy/CERN–SL obvious area of primary technology transfer interest is biomedical applications of CERN The project investigated the improvement of technologies, such as accelerators for radiation insulator performance by surface treatment, therapy and production of medical isotopes, including preparation methodology, surface sensors, effects of ionizing radiation, imaging, treatment, cleaning techniques and conditioning. simulation.

Subject: Thin film catalyst coating for improving vacuum Project: MEDIPIX

Contact: C. Benvenuti/CERN–EST The Medipix project aims to design, test and evaluate CMOS readout ASIC for semiconductor Sputter-coated catalyst thin films (e.g. Pd or Pd pixel detectors. The chip allows counting of alloys) do not oxidize when exposed to air. single photons in contrast to traditional charge Therefore their life is unlimited and no heating is integrating systems like film or CCD. This required for their activation. Catalyst coatings reduces background noise, which should lead to a may be used as an overlayer to protect thin-film larger signal-to-noise ratio and higher dynamic NEG coatings against oxidation range. X-ray imaging applications should profit

370 Technological Developments at CERN in 2000 from this contrast enhancement and medical X- – Giessen University, DE ray diagnosis should profit from dose reduction. – Grenoble University, FR – Lyon I, LPCML, Lyon, FR Collaborators: – Lyon I, IPNL, Lyon, FR – CERN, CH – Milan INFN & University, IT – Commissariat à l’Energie Atomique, CEA, – Minsk University, Belarus LETI, Saclay, FR – Moscow State University, RU – Czech Technical University, Prague, Czech – Muenchen MRI, DE Republic – Pisa University, IT – Institut de Fisica d’Altes Energies IFAE, X- – Prague CAS, Prague, Czech Republic ray group, Universitat Autonoma de – Rome INFN, IT Barcelona, Bellaterra, ES – Saclay DAFNIA, FR – Medical Research Council, Laboratory of – Valencia University, ES Molecular Biology (LMB), Cambridge, UK – Bogoroditsk Plant, RU – Mid-Sweden University, Sundsvall, SE – Karl Korth, DE – National Institute for Nuclear and High- – Hitachi Chemical, JP Energy Physics NIKHEF, Medipix Group, – Mitsui Mining and Melting NK&k, JP Amsterdam, NL – Crytur, Czech Republic – University of Cagliari, Department of – Optovac, USA Physics, Cagliari, IT –Crismatec, FR – Universität Freiburg-i.B., Fakultät für – SIC, Shangai, CN Physik, Freiburg, DE – Le Verre Fluoré, FR – University of Glasgow, Department of –CTI, USA Physics, Glasgow, UK – Scionix, NL – University of Naples, Physics Department, Medical Physics, Naples, IT – Siemens AG, DE – INFN &University of Pisa, Department of – LETI, FR Physics, Pisa, IT – University of Sassari, Department of Project: Hybrid photodetector tubes for Physics, Sassari, IT gamma spectroscopy and optoelectronic cameras – European Synchrotron Radiation Facility (ESRF) Grenoble, FR The Imaging Silicon Pixel Array (ISPA) tube is a hybrid photo-detector including a highly segmented pixel anode designed for scintillating Project: Crystal Clear fibres and RICH detectors. Coupled with a Development of inorganic scintillators (lead scintillating crystal it can provide gamma tungstate crystals). imaging with sub-millimetre accuracy for medical scintigraphy. A prototype is designed for Collaborators: medical application. – CERN, CH – Annecy, LAPP, FR Collaborators: – Brussels IIHE VUB-ULB, BE – CERN, CH – Copernicus University, Torum, PL – INFN, Rome III University, IT – Delft Technical University, NL – Prague Academy of Science, Czech – Geneva University Hospital & University of Republic Lausanne, CH –DEP, NL

Technological Developments at CERN in 2000 371 – Crytur Ltd, Czech Republic Project: Cristal Data Management System Project to monitor and control the production – Edgetek, FR and assembly process of CMS ECAL –PMB Metaceram, FR (electromagnetic calorimeter) – LIP Lisbon, PT Distributed data management system facility for tracking processes and product lifecycles and for the exploitation and operation of the construction Project: LIBO (LInac BOoster) data of the CMS detector. The LInac BOoster (LIBO) is a compact and low- cost proton linac designed for deep-seated tumour Objectives: Provide an information system to hadron therapy. The mechanical parts of cells and control quality during the construction processes; bridge couplers have been manufactured at the monitor the global production process across EST-MF Main Workshop using computer distributed centres; capture and store data during controlled machines, and successfully high detector construction; integrate instruments used temperature vacuum brazed at the EST-SM to characterize and measure products; provide laboratory. In November 2000, the module was controlled multiuser access to the production installed in the tunnel of the Linear Accelerator management system; provide customized access for LEP (LIL) and powered up by a 3 GHz to engineering data for CMS users. klystron reaching an average accelerating field of Collaborators: about 30 MV/m. – CERN, CH Collaborators: – LAPP, Annecy, FR – CERN, CH – University of West England, Bristol, UK – INFN, Milan, IT – University of Rome, INFN, Rome, IT – INFN, Naples, IT – IN2P3 and Department of the Haute- – TERA Foundation, IT Savoie, FR. – Scanditronix-IBA Project: Proton-Ion Medical Machine Study (PIMMS) Project: Compton camera The Proton-Ion Medical Machine Study In nuclear imaging techniques, Single Photon (PIMMS) group was formed following an Emission Computed Tomography (SPECT) and agreement between the Med-AUSTRON Positron Emission Tomography (PET) become (Austria) and the TERA Foundation (Italy) to more and more important. A typical application combine their efforts in the design of a cancer in nuclear imaging is to mark an organ with a therapy synchrotron. CERN agreed to host this tracer. study in its PS Division and a close collaboration Collaborators: was set up with GSI (Germany). The study group was later joined by Onkologie-2000 (Czech – CERN, CH Republic). – University of Michigan, USA – Institute of Nuclear Physics, Cracow, PL Collaborators: – LEPSI, IN2P3/CNRS-ULP, Strasbourg, FR – CERN, CH – HEP Group Valencia University, ES – Med-AUSTRON, AT – IDE AS, Oslo, NO – TERA Foundation, IT – University of Ljublijana, Slovenia – Onkologie 2000, Czech Republic

372 Technological Developments at CERN in 2000 Project: apeNEXT – A quality management of CERN and LHC ApeNEXT is a mutli-teraflop Lattice Gauge technical data Theory (LGT) computer that is being developed – Keeping data over a long period of time (the as the next generation of the family of existing LHC machine and the experiments have an APE LGT machines. estimated life-time of 25 years from the design stage to the decommissioning) with Collaborators: Worldwide access to data (Web Interface) – CERN, CH – INFN &Rome University, ‘La Sapienza’, IT Project: CoDisCo - Connecting Distributed – INFN & Parma University, IT Competencies – Roma University II ‘Tot Vergata’, IT The Connecting Distributed Competencies – INFN & University of Milan - Bicocca, IT (CoDisCo) project has lived up to its name; – DESY, Zeuthen, DE expertise ranging from project management, –Orsay, FR networking, WWW-based tools, management processes and benchmarking have been collected, Project: Ultrasonic gas analyser compiled, refined, and implemented among the An ultrasonic gas analyser has been developed to project consortium. The preset objectives for the meet a need for radiator gas analysis in ring project have been attained and with the active imaging Cherenkov detectors as well as to interaction among the project partners various measure perfluorocarbon vapour mixtures and unplanned results have been produced throughout xenon, helium or nitrogen gases. the creative collaboration.

Collaborators: Collaborators: – CERN, CH – CERN, CH – Centre Physique de particules de Marseille, – Finnyards, FI FR – Helsinki Institute of Physics, FI – Honnun og radgjof , IS Project: CEDAR (CERN EDMS for Detectors and AcceleratoRs) –IGP/NSP, NO CERN Engineering Data Management System – Kockums Computer Systems, SE for Detectors and Accelerators with the objective: – Logimatic, DK

Technological Developments at CERN in 2000 373

Seminars & Colloquia*

* Unpublished

CAS Accelerator Seminar A new method for non-linear and non-stationary time series analysis: the Hilbert spectral analysis The Sixteenth Lecture in the John Adams N. E. Huang (Laboratory for Hydrospheric Memorial Lecture Series Process, NASA Goddard Space Flight Center) (10.07.2000) The TESLA Test Facility and the first FEL for the vacuum ultraviolet X-rays from comets - a surprising discovery J. Rossbach (DESY, Hamburg) (24.11.2000) K. Dennerl (Max Planck Institute for Extraterrestrial Physics, Garching) (12.10.2000)

CERN Colloquia Cosmology without a beginning G. Veneziano (CERN-TH / Orsay-LPT (Chair B. Seeds of cosmic structure: quantum fluctuations Pascal)) (07.12.2000) in the primordial soup R. Kolb (Fermilab & University of Chicago) (17.01.2000) CERN EP Seminars

Recent results from the ZEUS experiment Black holes and gamma ray bursts J. Vossebeld (CERN) (10.01.2000) R. Ruffini (ICRA and University of Rome ‘La Sapienza’) (20.01.2000) Searching for exotic particles at NuTeV J. Formaggio (Columbia University) A confrontation with infinity (06.03.2000) G.’t Hooft, Nobel Laureate in Physics 1999 (University of Utrecht) (08.02.2000) Search for neutrino oscillations at the Palo Verde nuclear reactors. L. Miller (Stanford University) (20.03.2000) Extrasolar planets searches: today and tomorrow D. Queloz (Geneva Observatory) (18.05.2000) Dark matter searches: status and prospects A. Giuliani (University of Como & INFN Milano) History in space: the Italian quintet for (17.04.2000) astrophysics and planetary exploration G. Bignami (Italian Space Agency (ASI) and The Fermilab neutrino program University of Pavia, Italy) (22.06.2000) A. Para (FNAL) (22.05.2000)

Seminars & Colloquia 375 Recent FOCUS (FNAL-E831) results on charm Tilted pion sources from azimuthally sensitive mixing and CP violation HBT interferometry L. Moroni (INFN, Milano) (15.05.2000) U. Wiedemann (CERN) (04.04.2000)

New particles searches at CDF and the Tevatron The elusive EoS: Summary of the EoS2000 Workshop at GSI J. Goldstein (FNAL) (24.07.2000) P. Braun-Munzinger (GSI) (19.05.2000)

Recent QCD results from CDF What hadron production at SPS tells us about A. Korytov (University of Florida) (02.10.2000) properties of QGP equation of state J. Rafelski (University of Arizona, Tucson) Physics results from Belle (31.05.2000) A. Satpathy (KEK and Cincinnati University) (12.10.2000) Measures of critical behaviour at quark–hadron phase transition R. Hwa (University of Oregon) (07.06.2000) CERN Heavy-Ion Forums The microscopic origin of the strangeness enhancement at the SPS The role of ‘additive quark’ dynamics in stopping S. Vance (Brookhaven National Laboratory) and strangeness production in nuclear collisions (20.06.2000) at the AGS B. A. Cole (Columbia University, New York) The colored glass condensate and extreme QCD (02.02.2000) L. McLerran (Brookhaven National Laboratory) (20.06.2000) The QCD equation of state at finite temperature F. Karsch (CERN and University of Bielefeld) Jet correlation and scale-local measures (18.02.2000) T. A. Trainor (University of Washington, Seattle) (20.06.2000) Photons and dileptons from the quark–gluon plasma First NA49 results on 40 GeV / nucleon and energy dependence of pion and strangeness M. Thoma (CERN-TH) (17.03.2000) production M. Gazdzicki (IKF, Frankfurt) (03.10.2000) Implication of percolation of colour strings on multiplicity, correlations and the transverse Hadronization and heavy-ion collisions at the momentum SPS M. Braun (St. Petersburg State University) T. A. Trainor (Univ. of Washington, Seattle) (17.03.2000) (16.10.2000)

Phi-measure of event-by-event fluctuations p+A physics at SPS (18.10.2000): S. Mrowczynski (Warsaw) (27.03.2000) Results from NA49 on p+A Fluctuation Probes of Quark Deconfinement A. Rybicki (Institute of Nuclear Physics, Cracow, U. Heinz (CERN-TH) (27.03.2000) Poland)

376 Seminars & Colloquia Exciting physics with pA collisions Recent NA49 results on unlike particle P. Kopeliovich (MPI Heidelberg) correlations in Pb+Pb collisions at 160 AGeV R. Lednicky (Institute of Physics, Prague and Baryon stopping and strange baryon production MPI, Munich) in p+A and pbar+A collisions A. Capella (LPTHE, Orsay) Correlation search for coherent pion emission in heavy-ion collisions Elliptic flow at RHIC Y. Sinyukov (Bogolyubov ITP, Kiev and A. Poskanzer (LBNL) (24.10.2000) Subatech, Nantes)

Results from CERES/NA45 on flow at 40 AGeV M. Gazdzicki (CERN) (24.10.2000) Observation of dijet-like correlations between charged pions of high-transverse momentum Anisotropic transverse flow and the quark hadron produced in 158 GeV/c Pb–Au collisions phase transition J. Rak (Univ. of Heidelberg) (05.12.2000) P. Kolb (Univ. of Regensburg) (24.10.2000) A new rescattering mechanism for quarkonium First results from RHIC production G. Roland (MIT) (30.10.2000) S. Peigne (LAPP, Annecy) (05.12.2000)

On particle correlations (14.11.2000): CERN Informatics Tutorials

Introduction Netscape 4.7 : ce que vous utiliserez le mois U. Wiedemann (CERN) prochain ! A. Taddei (CERN) (15.02.2000) Meson Correlations in Au+Au collisions at sqrt_s+130 GeV Netscape 4.7 : ce que vous utiliserez le mois S. Panitkin (BNL) prochain ! A. Taddei (CERN) (22.02.2000) Three-pion interferometry from the WA98 experiment in central 158 AGeV Pb+Pb The Java Series: Basic concepts in object oriented collisions programming L. Rosselet (Univ. of Geneva) R. Ramos Pollan (CERN) (25.02.2000)

Multi-boson effects in Bose–Einstein The Java Series: Basic concepts in object oriented interferometry programming U. Heinz (CERN) R. Ramos Pollan (CERN) (03.03.2000)

A program of close velocity correlation studies Java Series: Java Essentials I. What is Java. Basic for ALICE language constructs J. Pluta (Warsaw University of Technology) R. Ramos Pollan (CERN) (03.03.2000)

Seminars & Colloquia 377 Java Series: Java Essentials II. Advanced Developing with plugins and components language constructs P. Valenca (CERN) (11.07.2000) R. Ramos Pollan (CERN) (07.03.2000) The Java Series: Basic concepts in object- Netscape 4.7 : ce que vous utiliserez le mois oriented programming prochain ! R. Ramos Pollan (CERN) (18.07.2000) A. Taddei (CERN) (07.03.2000) The Java Series: Java Essentials I. What is Java. The Java Series: GUI building with AWT Basic language constructs R. Ramos Pollan (CERN) (10.03.2000) R. Ramos Pollan (CERN) (21.07.2000)

The Java Series: GUI building with Swing The Java Series: Java Essentials II. Advanced R. Ramos Pollan (CERN) (14.03.2000) language constructs R. Ramos Pollan (CERN) (25.07.2000) The Java Series: I/O, object serialisation and persistence The Java Series: GUI building with AWT R. Ramos Pollan (CERN) (27.07.2000) R. Ramos Pollan (CERN) (17.03.2000)

The Java Series: GUI building with Swing The Java Series: Network and WWW R. Ramos Pollan (CERN) (01.08.2000) programming. Servlets R. Ramos Pollan (CERN) (21.03.2000) The Java Series: I/O, object serialisation and persistence The Java Series: Introduction to JDBC R. Ramos Pollan (CERN) (22.08.2000) R. Ramos Pollan (CERN) (24.03.2000)

The Java Series: Network and WWW The Java Series: Distributed objects with RMI programming. Servlets and Corba R. Ramos Pollan (CERN) (25.08.2000) R. Ramos Pollan (CERN) (14.04.2000)

The Java Series: Introduction to JDBC The Java Series: Introduction to JNI R. Ramos Pollan (CERN) (28.08.2000) R. Ramos Pollan (CERN) (17.04.2000) The Java Series: Distributed objects with RMI The Java Series: Using the Java Beans and Corba architecture R. Ramos Pollan (CERN) (01.09.2000) R. Ramos Pollan (CERN) (02.05.2000) The Java Series: Introduction to JNI Introduction to FrontPage R. Ramos Pollan (CERN) (05.09.2000) A. Pace (CERN) (26.05.2000) The Java Series: Using the Java Beans Introduction aux services Web au CERN architecture A. Pace (CERN) (30.05.2000) R. Ramos Pollan (CERN) (12.09.2000)

Introduction à FrontPage (en français) Introductory overview to Adobe InDesign A. Pace (CERN) (09.06.2000) A. Zombath (ID-Form S.A.) (26.09.2000)

378 Seminars & Colloquia SIMBA - The new web interface for Listbox The onset of deconfinement in nucleus–nucleus owners collisions at the SPS M. Ganz and Ray Jackson (CERN) (27.10.2000) P. Seyboth (Max-Planck-Institut fuer Physik, Munich) (11.07.2000)

CERN Particle Physics Seminars Whither WIMPs - CDMS, DAMA and the search for 30% of the missing mass of the Universe Accelerating and scattering polarised protons R. Gaitskell (UC Berkeley, USA) (17.07.2000) A. Krisch (University of Michigan, USA) (18.01.2000) Highlights of the ICHEP 2000 Osaka Conference N. Ellis (CERN) (12.09.2000) New measurement of direct CP violation in two- pion decays of neutral kaons by NA48 at CERN First observation of tau neutrino A. Ceccucci (CERN) (29.02.2000) K. Niwa (Nagoya University) (19.09.2000)

The NOMAD search for neutrino oscillations R. Petti (CERN) (14.03.2000) Images of the primeval Universe from the BOOMERanG experiment The structure of the photon P. de Bernardis (Università di Roma ‘La R. Nisius (CERN) (11.04.2000) Sapienza’) (03.10.2000)

First physics from BABAR Binary stars and the conundrum called Cygnus J. Fry (University of Liverpool, UK) (02.05.2000) X-3 J. Bell Burnell (The Open University, Milton First experience with Kloe at DAFNE Keynes, UK) (24.10.2000) P. Franzini (University of Rome, La Sapienza) (09.05.2000) Recent results of the LEP combined Higgs searches Glueballs and the Pomeron - a central mystery C. Tully (Princeton University) (08.11.2000) F. Close (Rutherford Appleton Laboratory, UK) (16.05.2000) Update on the L3 Higgs Candidates C. Tully (Princeton University) (14.11.2000) Status of the ICANOE Project A. Rubbia (ETH, Zurich) (31.05.2000) First results from Belle M. Yamauchi (KEK, Japan) (24.11.2000) Neutrino oscillation physics at a Neutrino Factory P. Hernandez (CERN) (13.06.2000) The physics programme of ELFE Prospects for the Neutrino Factory - a report from D. Ryckbosch (University of Ghent, Belgium) Monterey (28.11.2000) K. Peach (Rutherford Appleton Laboratory, UK) (20.06.2000) Final neutrino oscillation results from the LSND experiment Highlights of the Neutrino 2000 Conference G. Mills (Los Alamos National Laboratory) D. Autiero (CERN) (04.07.2000) (05.12.2000)

Seminars & Colloquia 379 L’ usine a neutrinos Global computing technology outlook S. Gilardoni (DPNC, Université de Genève) D.F. McQueeney (IBM Research) (28.09.2000) (06.12.2000) What comes next in Internet infrastructure Solar variability, cosmic rays and climate change B. E. Carpenter (IBM) (11.10.2000) M. Lockwood (Rutherford/Appleton Laboratory and Southampton University) (12.12.2000) Computing Seminars Study of the Standard Model gauge couplings and search for anomalous quartic couplings in L3 Grid computing: resource sharing and M. Biglietti and M. Musy (DPNC, Université de coordinated problem solving in scalable Genève) (20.12.2000) distributed communities I. Foster and C. Kesselman (Argonne National Laboratory and the University of Chicago / Computing Colloquia University of Southern California Info) (17.01.2000) Computational and data grids - are they important? MLPfit: a simple and powerful tool for training P. Messina (ASCI) (18.01.2000) and using Multi-Layer Perceptrons J. Schwindling (CEA, Saclay) (19.01.2000) The application of semi-formal and formal techniques within the software life cycle of safety Highlights from CHEP 2000 critical applications B. Segal, A. Pfeiffer and M. Nowak (CERN) F. Giunchiglia (ITC/IRST & University of Trento) (16.02.2000) (02.02.2000) Searching multiple Web servers in HEP Quantum computing (defect-tolerant molecular V. Sivunen (CERN) (23.02.2000) nanoelectronics) R. Stanley Williams (Hewlett-Packard Testing object-oriented software Laboratories) (30.05.2000) M. Roper (Dept. Computer Science, University of Strathclyde, Glasgow, UK) (08.03.2000) Information integration & database mediation G. Wiederhold (Mediation Technology Database Archiving of electronics designs with EDMS Group, Stanford University) (19.06.2000) P. Farthouat (CERN) (10.05.2000)

Ontology-driven information integration: the The Trillian Project research perspective from the DWQ project and S. Jarp (CERN) (17.05.2000) the experience from the TAMBIS project E. Franconi (Department of Computer Science, The MAP Project University of Manchester, UK) (19.06.2000) T. Bowcock (Liverpool University) (31.05.2000)

Linux clustering and storage management Experiences during the 2000 ALICE Data P. J. Braam (Chief Architect, TurboLinux) Challenge (21.07.2000) P. Vande Vyvre (ALICE) (07.06.2000)

380 Seminars & Colloquia A vector math library for IA-64 Detector Seminars C. Roothaan (HP Labs) (14.06.2000) History and mystery of micro strip gas chambers Part 1: Cjj: a subset of C++ compliant with Java A. Cattai (CERN) (04.02.2000) Part 2: Reverse engineering of the UML class diagram from C++ code in presence of weakly Infrared scintillation and emission in gases, typed containers liquids and crystals P. Tonella (ITC-irst) (12.07.2000) G. Carugno (INFN-Padova) (25.02.2000)

High performance networking for data grids Construction and commissioning of the CLEO III B. Tierney (CERN and LBNL) (25.10.2000) detector and its RICH G. Viehhauser (Syracuse University) Electromagnetic simulation tools: from (24.03.2000) accelerators to detectors

T. Motos Lopez (CERN) (01.11.2000) Silicon pad detectors for tracking and particle identification in heavy ion collisions High-level system design using Foresight H. Pernegger (Massachusetts Institute of G. Dim marzo - Serugendo (CERN) (01.11.2000) Technology) (31.03.2000)

HPSS 4.1.1 on Compaq Tru64 Unix P. Calegari (CERN) (08.11.2000) Duality Workshop

Experience with the CASTOR mass storage Holography for non-critical superstrings system: Practical, design and development issues A. Giveon (CERN) (25.01.2000) J.-D. Durand (CERN) (08.11.2000)

AdS-Flows, Weyl Gravity, and the cosmological Object oriented Ntuple/tag analysis in Anaphe/ constant LHC++ Z. Molnar (CERN) (15.11.2000) C. Schmidhuber (CERN) (15.02.2000)

Next generation HTML rendering in GNOME Confinement and the AdS/CFT correspondence D. Lundin and A. Carlsson (CodeFactory AB, M. Parikh (Utrecht) (29.02.2000) Sweden) (22.11.2000) Stable non-BPS branes of type I Integration of LDAP into the messenging L. Gallot (University of Torino) (07.03.2000) infrastructure at CERN R. Jackson (CERN) (29.11.2000) Vertex operators for the supermembrane and matrix theory H. Nicolai (Universität Hamburg) (21.03.2000) Cosmology Workshop Introductory lectures on boundary conformal Double supersymmetric inflation field theories - I J. Lesgourgues (SISSA) (17.01.2000) J.B. Zuber (Saclay) (04.04.2000)

Seminars & Colloquia 381 Introductory lectures on boundary conformal Closed strings from decay of unstable open string field theories - II vacua J.B. Zuber (Saclay) (06.04.2000) P. Yi (Columbia University) (22.08.2000)

Stability and BPS branes Towards BPS spectra of general N = 2 Yang– C. Roemelsberger (Rutgers University) Mills theories (11.04.2000) P. Yi (Columbia University) (24.08.2000)

Coulomb branch of gauge theories in AdS/CFT Microscopic pictures of dynamical symmetry A. Brandhuber (CERN) (23.05.2000) breaking in supersymmetric gauge theories K. Konishi (Pisa University) (29.08.2000) From branes at singularities to particle physics A. Uranga (CERN) (30.05.2000) Post-Riemannian merger of Yang–Mills interactions with gravity Open strings in the background of NS 5-branes O. Megged (Tel Aviv) (31.08.2000) A. Giveon (CERN) (06.06.2000)

Supergravity description of non-BPS branes Green–Schwarz action in AdS5 x s5 in light-cone G. Mandal (CERN) (13.06.2000) gauge A. Tseytlin (Ohio University) (05.09.2000) Micrometer gravitinos and the cosmological constant Review of non-commutative string theory C. Schmidhuber (CERN) (20.06.2000) J. Fernandez-Barbon (CERN) (17.10.2000)

Space–time non-commutativity in string theory Chaos in superstring cosmology J. Gomis (Caltech) (04.07.2000) M. Henneaux (Université Libre de Bruxelles) (24.10.2000) Aspects of the BTZ black hole D. Birmingham (National University of Ireland, Perturbative dynamics of non-commutative Dublin) (11.07.2000) Yang–Mills theory A. Armoni (Ecole Polytechnique) (14.11.2000) NS-NS branes as topological solitons in brane antibrane systems Partial non-renormalization of the stress-tensor Y. Lozano (CERN) (18.07.2000) four-point function in N = 4 SYM and AdS/CFT B. Eden (LAPTH, Annecy) (28.11.2000) CFT & FRW E. Verlinde (Princeton) (25.07.2000) Aspects of supersymmetry and supergravity in The irreversibility of the rg flow in even and odd higher dimensions - I dimensions S. Ferrara (CERN) (05.12.2000) D. Anselmi (CERN) (08.08.2000) Aspects of supersymmetry and supergravity in On D- and NS5-instantons on K3 higher dimensions - II E. Kiritsis (University of Crete) (15.08.2000) S. Ferrara (CERN) (12.12.2000)

382 Seminars & Colloquia ETT Seminars Presentation of SIMATIC S7 communication protocol (06.10.2000) Intellectual property licensing at SRI International Data consistency C. Raymond Perrault (SRI International) P. Stühler (SIMATIC System Design Department) (08.06.2000) and A. Lehmann

Mediation technology Communication between SIMATIC and HMI- Wiederhold (Mediation Technology, Database systems (incl. live presentation) Group, Stanford University) (19.06.2000) N. Schwoerer (HMI Department for High-End HMI Systems) Ontology-driven information integration: the research perspective from the DWQ project and the experience from the TAMBIS project Présentation des nouvelles possibilités des E. Franconi (Department of Computer Science, équipements PREMIUM dans le cadre du University of Manchester, UK) (19.06.2000) partenariat CERN/Schneider Ph. Bourdet, R. Brun, S. Catherineau et al. Intellectual property rights and patent protection (CERN) (14.11.2000) D. Weber-Bruls (Forrester & Boehmert) (01.11.2000)

LHC Project Seminars Exceptional Seminars LHC project management Supersymmetry anomaly P. Faugeras (CERN) (13.01.2000) Y. Shamir (Tel Aviv University) (24.01.2000) The LHC Quality Assurance Plan Non-equilibrium aspects of the chiral phase M. Mottier (CERN) (03.02.2000) transition in heavy-ion collisions D. Boyanovsky (Univ. Pittsburgh) (26.05.2000) EDMS tools to support the LHC project T. Pettersson (CERN) (17.02.2000) Probing the matter term at long baseline neutrino experiments Results from the LHC inner triplet quadrupole S. U. Sankar (Bombay) (23.06.2000) model magnet program at Fermilab J. Kerby and J. Strait (Fermilab) (20.04.2000) Relativistic wave equations for interacting massive particles with arbitrary half-integer spins Photodesorption studies at cryogenic J. Niederle (Prague) (16.11.2000) temperatures for accelerator applications V. Baglin (CERN) (15.06.2000)

GUAPI Seminars Contributions of the LHC Division to EPAC2000 V. Baglin (CERN) (23.06.2000) Développements envisagés dans le cadre du partenariat CERN–Schneider The LHC dipole magnets R. Brun (CERN) (20.09.2000) C. Wyss (CERN) (13.07.2000)

Seminars & Colloquia 383 Advances in magnet design and optimisation Computer-supported indexing S. Russenschuck, M. Aleksa and C. Vollinger M. Guenardi (Lexicographer, NASA CASI) (CERN) (28.09.2000) (16.05.2000)

Future accelerators and R&D at CERN Update on electronic journals at the American K. Hübner (Director of Accelerators, CERN) Physical Society (23.11.2000) M. C. Foster (Assistant Editor, Physical Review) (20.09.2000) Heavy ion physics with the ALICE detector at the LHC E-journals at OhioLINK J. Schukraft (CERN) (07.12.2000) C. Pitts Diedrichs (Ohio State University Library) (17.10.2000)

LHC Special Seminars Meeting on Particle Physics Tools for reduction and analysis of large batches Phenomenology of experimental data, with application to the cryogenic thermometry for the LHC The uses of low-energy solar neutrinos P. Ciarlini and D. Ichim (IAC Roma) and A. De Gouvea (CERN) (21.01.2000) F. Pavese (IMGC, Torino) (11 and 12.09.2000) Recent developments in small-x physics Spatially resolved plasma diagnostics by optical G. Salam (CERN) (28.01.2000) interferometry T. Neger (Technische Universität Graz) Higgs and electroweak precision physics at (05.10.2000) present and future colliders G. Weiglein (CERN) (04.02.2000)

Library Science Talks Hadronic multiplicities in diffractive and non- diffractive DIS Literature in Focus A. Kisselev (IHEP and CERN) (11.02.2000) Landolt Boernstein: transition into the electronic age (30.03.2000) Flavour problem, proton decay and neutrino oscillations in SUSY models with anomalous What’s new about Landolt Boernstein U(1) W. Martienssen (Editor in Chief Landolt Z. Tavartkiladze (Institute of Physics, Georgia) Boernstein, Frankfurt/M) (18.02.2000)

How to use Landolt Boernstein New Series in Effective chiral Lagrangians for heavy mesons view of new developments and the unitarity triangle H. Schopper (CERN) G. Nardulli (CERN) (25.02.2000)

The LINK-server of Springer Verlag: status and The relation between the MS and the on-shell future developments quark mass at order G. Griepke (Springer Verlag, Heidelberg) M. Steinhauser (University of Hamburg) (03.03.2000)

384 Seminars & Colloquia Recent developments in calculating power Linking fermion masses, neutrino oscillations corrections to hadronic event shapes and CP violation through supersymmetric Z. Trocsanyi (CERN) (10.03.2000) unification J. Pati (University of Maryland) (07.07.2000)

Measuring Vub without solving QCD Z. Ligeti (Fermilab) (17.03.2000) Spin correlations and polarization effects in the MSSM Theory of rare kaon decays G. Moortgat-Pick (DESY) (14.07.2000) G. D’Ambrosio (INFN, Napoli) (24.03.2000) The cp violating angles α and β from b decays to Hadronic three-jet production at NLO three light pseudoscalar mesons W. B. Kilgore (Brookhaven) (31.03.2000) A. Deandrea (CERN) (28.07.2000)

Neutral Higgs boson search within SM and Two-loop effects in the MSSM MSSM at hadron colliders S. Heinemeyer (DESY) (25.08.2000) A. Belyaev (CERN) (14.04.2000) Influence of a medium on pair photoproduction Observation of the 0++ gluonium ground state in and bremsstrahlung antiproton annihilations at rest V. N. Baier (Budker Inst. of Nuclear Physics, U. Gastaldi (INFN Laboratori Nazionali di Novosibirsk) (15.09.2000) Legnaro and CERN) (05.05.2000) Survey of rare B decays: 1997–2003 Soft gluon resummations in DIS G. W. S. Hou (National Taiwan University) M. Dasgupta (INFN, Milano) (12.05.2000) (22.09.2000)

Prospects for intermediate mass Higgs studies at Higgs phenomenology of the minimal non- the LHC minimal supersymmetric standard model D. Zeppenfeld (UW Madison and CERN) A. Pilaftsis (University of Würzburg) (19.05.2000) (29.09.2000)

RacoonWW: radiative corrections on The algebraic method + − e e → WW → 4F P. A. Grassi (New York University) (06.10.2000) S. Dittmaier (University of Bielefeld) (09.06.2000) Improving the perturbative predictions for BXs→ γ Signals of non-standard physics in distributions M. Misiak (CERN) (13.10.2000) of top-quark decay products at linear colliders B. Grzadkowski (University of Warsaw) Twelve years of precision calculations for LEP. (16.06.2000) What’s next? D. Bardin (JINR, Dubna) (20.10.2000) Associated production of gauginos and gluinos at hadron colliders in next-to-leading order SUSY Calculating hadronic matrix elements of QCD exclusive B decays in QCD M. Klasen (University of Hamburg) (03.07.2000) A. Khodjamirian (CERN) (27.10.2000)

Seminars & Colloquia 385 Medium dependence of hard processes at LHC Study of a neutrino factory at Fermilab U. Wiedemann (CERN) (03.11.2000) N. Holtkamp (Fermilab) (05.07.2000)

Quintessential adjustment of the cosmological E-157: a plasma wakefield acceleration constant experiment A. Ebecker (CERN) (10.11.2000) P. Muggli (UCLA) (26.07.2000)

Jet physics in two-loop QCD: Recent Perspectives for radioactive beams at ISOLDE developments and open issues D. Habs (LMU, Münich) (27.09.2000) T. Gehrmann (CERN) (17.11.2000) Advances in plasma accelerators A new hyperfine operator for leptonium and R. Bingham (RAL) (18.10.2000) quarkonium H. Pilkuhn (University of Karlsruhe) (24.11.2000) RD49 Seminars Theory of jet production at HERA RD49 seminar on deep-submicron CMOS B. Pötter (MPI, Munich) (01.12.2000) technology Characterisation of statistical device property Next-to-next-to-leading logarithmic corrections fluctuations in deep-submicron CMOS at small transverse momentum in hadronic collisions H. Tuinhout (Philips Research Laboratories, Eindhoven, The Netherlands) (06.07.2000) D. De Florian (ETH Zürich) (08.12.2000)

High-energy asymptotics of QCD: BFKL and its RD49 seminar on COTS applications Trends in radiation susceptibility for advanced V. T. Kim (St. Petersburg Nuclear Physics Inst., semiconductor devices Russia and CERN) (15.12.2000) A. Johnston (NASA-JPL) (15.09.2000)

Study of radiation effects in microelectronic PS Seminars devices at Vanderbilt University (20.10.2000):

Optimum optical systems and new accelerators Modelling and stimulating radiation effects in microelectronics P. Royer (CERN) (09.02.2000) R. Schrimpf (Electrical Engineering and Computer Science Department, Vanderbilt Stabilising intense beams by linear coupling University, Nashville, TN 37235) E. Metral (CERN) (12.04.2000)

Radiation effects research at Vanderbilt Review of PS contributions for EPAC 2000 University (CERN) (21.06.2000) K. Galloway (Electrical Engineering and Computer Science Department, Vanderbilt A new configuration for two-beam linear University, Nashville, TN 37235) colliders R. Ruth (SLAC) (28.06.2000)

386 Seminars & Colloquia RD49 seminar on radiation hardened active pixel Coherent beam–beam modes in the LHC sensor (APS) M. Paz Zorzano (CERN) (02.03.2000) Activities in the area of radiation hard CMOS APS image sensors at photobit corporation Applications of a multiturn SPS orbit acquisition Dr. S. Eid (Columbia University, New York) system (14.11.2000) J. Klem (CERN) (23.03.2000)

RD49 seminar on 1/f noise in deep submicron Abnormal operating conditions of the LHC beam CMOS technology dump Reduction of 1/f noise in MOS transistors L. Bruno (CERN) (06.04.2000) B. Nauta (University of Twente, Enschede, The The Energy Amplifier Monte Carlo code package Netherlands) (06.12.2000) (EA-MC) - A new approach to the design of accelerator-driven systems Y. Kadi (CERN) (20.04.2000) Science and Society Seminars The Neutron Time Of Flight (nTOF) facility Changing perspectives on public understanding V. Vlachoudis ( CERN) (04.05.2000) of science in the UK P. Briggs (British Association for the LHC project management Advancement of Science) (04.02.2000) P. Faugeras (CERN) (11.05.2000)

Is evaluation of scientists objective? The TESLA klystron and modulator A. Wold (Dept of Clinical Immunology, Göteborg S. Choroba (DESY) (18.05.2000) University) (11.05.2000) Review of R&D needs for a Neutrino Factory Galileo Galilei: a poet against academia, in E. Keil (CERN) (08.06.2000) English for the first time G. F. Bignami (Italian Space Agency (ASI) and An almost deterministic automated matching University of Pavia, Italy) (21.06.2000) algorithm and preliminary tests at Jefferson Lab Y.-C. Chao (Jefferson Laboratory) (15.06.2000) Bridging the information gap in neuroscience Oral contributions to the European Particle M. Ellisman (University of California, San Accelerator Conference 2000 Diego) (18.12.2000) Participants at EPAC 2000 (CERN) (22.06.2000)

Signal processing for beam position monitors SL Seminars G. Vismara (CERN) (06.07.2000)

Study of CP violation with the experiment NA48 Neutrino physics at Gran Sasso C. Biino (INFN, Torino) (27.01.2000) C. Rubbia (CERN) (13.07.2000)

Conclusions from the Workshop on SL Neutrino oscillations and perspectives for the Performance, Chamonix X CNGS S. Myers (CERN) (10.02.2000) P. Strolin (CERN) (28.09.2000)

Seminars & Colloquia 387 SL contribution to CLIC studies Virtual and real photons radiated by the cooling F. Zimmermann (CERN) (26.10.2000) and hadronizing fireball J. Stachel (University of Heidelberg)

Special Colloquium Hadron signals of the little bang R. Stock (University of Frankfurt) From the pile of Volta to the fuel cells J.-F. Fauvarque (Conservatoire National des Arts Strange signals of a new state of matter from et Métiers (CNAM)) (28.03.2000) nuclear collisions at SPS E. Quercigh (CERN) Special Detector Seminar Summary Activities of the Centro Nacional de L. Maiani (CERN) Microelectrónica M. Huertas (Centro Nacional de Microelectrónica, Spain) (02.03.2000) Technical Seminars

A technical seminar about Diffpack - a powerful Special LEPC Seminar object-oriented software for the modelling, simulation and solving of PDE problems in LEP machine report industrial, scientific or research organisations S. Myers (CERN) E. Acklam (CERN) (24.05.2000) LEP detector reports D. Schlatter, T. Camporesi, J.-J. Blaising and C. Sécurité intégrée dans les PLCs Rembser (CERN) B. Mysliwiec (Siemens Nuremberg) (22.06.2000) LEP search working group reports C. Tully and S. Rosier-Lee (CERN) (05.09.2000) The LabVIEW 6i World Wide Tour at CERN S. Zanetti (LabVIEW/BridgeVIEW Product Manager, National Instruments Corporate, Special Seminar Austin, Texas), M. Farhi-Chevillard (Software Engineer LabVIEW, National Instruments A new state of matter: Results from the CERN Corporate, Austin, Texas) Lead-Beam Programme (10.02.2000): The next generation of BridgeVIEW S. Zanetti (LabVIEW/BridgeVIEW Product Making quark–gluon matter in relativistic nuclear Manager, National Instruments Corporate, collisions Austin, Texas) (29.09.2000) U. Heinz (CERN)

The J/ψ suppression pattern observed in Pb–Pb Optical fibre cables and terminated optical cable collision ions: a signature for the production of a assemblies new state of matter M. Farhi-Chevillard (Ericsson Cables, Sweden) L. Kluberg (IN2P3) (05.10.2000)

388 Seminars & Colloquia Theoretical Seminars New colour decompositions for gauge amplitudes V. Del Duca (CERN) (10.05.2000) Lattice QCD using domain wall quarks T. Blum (RIKEN BNL Research Center) Salutatory relaxation of the cosmological term in (12.01.2000) string theory J. March-Russell (CERN) (17.05.2000) The confining string and the c-theorem E. Alvarez (Universidad Autonoma de Madrid Five-dimensional N = 2 Yang–Mills/Einstein/ and CERN) (19.01.2000) Tensor supergravity theories and their vacua M. Gunaydin (CERN) (24.05.2000) Quantum gravity C. Rovelli (University of Pittsburgh, USA and The largest temperature of the Universe and its CPT Luminy, Marseille) (26.01.2000) cosmological implications A. Riotto (Scuola Normale Superiore, Pisa) (31.05.2000) Resummation of singlet structure functions at small x Neutrino masses and lepton-flavour violation in G. Altarelli (CERN) (02.02.2000) the light of Super-Kamiokande S. Lola (CERN) (07.06.2000) Weak scale strings and extra dimensions K. Benakli (CERN) (09.02.2000) Two-time physics I. Bars (University of Southern California) On the supergravity and Yang–Mills (14.06.2000) correspondence Y. Oz (CERN) (16.02.2000) Generalized Hall effects and the chiral anomaly J. Frohlich (ETH, Zurich) (21.06.2000) Brane world, supersymmetry and the cosmological constant Cosmology with extra dimensions R. Kallosh (Stanford and CERN) (23.02.2000) J. Terning (Harvard University) (05.07.2000)

QCD factorization for exclusive non-leptonic B Topological effects in our brane world from extra decays dimensions G. Buchallaz (CERN) (01.03.2000) M. Shifman (University of Minnesota) (12.07.2000) The little Big-Bang U. Heinz (CERN) (08.03.2000) New directions for new dimensions: from strings to neutrinos to axions and beyond B decays at the LHC K. Dienes (University of Arizona) (19.07.2000) P. Ball (CERN) (05.04.2000) D-branes on stringy calabi-yau manifolds Self-gravitating fundamental strings and black M. Douglas (Rutgers University) (26.07.2000) holes T. Damour (IHES, Bures-sur-Yvette) A gauge invariant exact renormalization group (12.04.2000) T. Morris (Southampton University) (02.08.2000)

Seminars & Colloquia 389 Self-duality: theme and variations Global QCD analysis and parton distributions - B. Pioline (Harvard University) (09.08.2000) end of the road or dawn of a new era? W.-K. Tung (Michigan State Univ. and CERN) Monte Carlo simulation of LHC physics (15.11.2000) B. Webber (Cambridge University and CERN) (16.08.2000) Living inside a hedgehog M. Shaposhnikov (Université de Lausanne) Towards the large N limit of N = 1 Yang Mills (22.11.2000) J. Maldacena (Harvard University) (23.08.2000) Non-relativistic two-body systems in quantum field theory Neutrino oscillations and Big Bang A. Hoang (CERN) (29.11.2000) nucleosynthesis A. Dolgov (Copenhagen; ITEP, Moscow; INFN, Intermediate scale string phenomenology Ferrara) (30.08.2000) B. Allanach (CERN) (13.12.2000)

Is the up quark massless? A reappraisal from first principles H. Wittig (CERN) (06.09.2000) Thursday Seminars

Kinoshita–Lee–Nauenberg theorem and thermal Neutrino masses and the baryon asymmetry photon production W. Buchmuller (DESY) (20.09.2000) H. Zaraket (LAPP, Annecy) (03.02.2000)

Physics with large extra dimensions Neutrino oscillations and SO(10) unified theories I. Antoniadis (CERN) (27.09.2000) F. Buccella (INFN and University of Naples) (10.02.2000) Synthesis of the light elements: D to B

K. Olive (Univ. of Minnesota and CERN) Multihadron production at high-energy collisions (04.10.2000) L. Popova (INR / Sofia) (24.02.2000)

Flow in ultrarelativistic nuclear collisions Gluon–meson duality J.-Y. Ollitrault (Service de Physique Théorique, C. Wetterich (Heidelberg) (02.03.2000) Saclay) (18.10.2000)

Statistics of clustering and models of ultra-high- Anomalous pulsars: magnetars or quark stars? energy cosmic rays A. Dar (CERN) (25.10.2000) P. Tinyakov (Lausanne) (09.03.2000)

What if the Higgs boson weighs 115 GeV? Aspects of chiral dynamics in QCD at finite J. Ellis (CERN) (01.11.2000) density M. Tytgat (CERN) (16.03.2000) Generalized (non-Abelian, supersymmetric) fluid mechanics (and D-branes) A theory of jet definition R. Jackiw (M.I.T.) (08.11.2000) F. Tkachov (Moscow) (23.03.2000)

390 Seminars & Colloquia A critical look at safety analyses for RHIC and More about all current algebraic orbifolds ALICE M.B. Halpern (LBL) (22.06.2000) A. Kent (DAMTP, Cambridge) (30.03.2000) Quintessence and space-time geometry from the Geophysical constraints on mirror matter within first CMB Doppler peak the earth P. Frampton (North Carolina University) A. Ignatiev (University of Melbourne) (06.07.2000) (06.04.2000) The primordial spectrum of gauge fields from Wess–Zumino term and orbifold projection in inflation and preheating N=1 SQCD with quantum modified moduli space O. Tornkvist (DAMTP, Cambridge) (13.07.2000) S. Dubovsky (INR, Moscow and Univ. of Lausanne) (13.04.2000) A degenerate relic neutrino background for primordial nucleosynthesis Superconformal symmetry and the Maldacena G. Miele (University of Naples) (20.07.2000) Conjecture P. West (King’s College London and CERN) Gauged Holography (19.04.2000) M. Porrati (New York University) (27.07.2000)

Baryogenesis via the electroweak phase Microlensing searches of dark matter transition: the options remaining E. Roulet (La Plata University) (03.08.2000) M. Laine (CERN) (26.04.2000)

Deformed Lorentz symmetry and high-energy Creation of pre-Big-Bang universes from astrophysics colliding plane waves L. Gonzalez-Mestres (LAPP, Annecy) K. Kunze (University of Geneva) (04.05.2000) (17.08.2000)

Entropy and phases of chiral gauge theories Superluminal signals from gamma ray bursts F. Sannino (Yale) (11.05.2000) A. Dar (Technion) (21.09.2000) Neutralino dark matter is dead, unless… P. Gondolo (MPI, Munich) (18.05.2000) Excitations in hot non-commutative theories E. Lopez (CERN) (28.09.2000) On the possible manifestation of the dilaton in neutron and boson stars Effective field theories for non-relativistic P. Fisiev (Univ. Sofia) (25.05.2000) systems A. Pineda (CERN) (05.10.2000) Are fermions just ‘als ob’: deriving SUSY formally Van Hove singularities in high-temperature QCD H.B. Nielsen (CERN) (08.06.2000) M. Thoma (CERN) (12.10.2000)

Pulsar acceleration by asymmetric emission of Ultra-high-energy cosmic rays and new particle sterile neutrinos physics E. Nardi (Medellin) (15.06.2000) M. Kachelriess (CERN) (19.10.2000)

Seminars & Colloquia 391 Axinos - new candidate for cold dark matter Journée de l’audition au CERN L. Roszkowski (CERN) (02.11.2000) R. Gaitskell (CERN) (07.03.2000)

Cosmological vorticity perturbations, European Directive 97/23/EC on pressure gravitomagnetism and Mach’s principle equipment and its influence on CERN Safety C. Schmid (ETH, Zurich) (16.11.2000) regulations D. Koplewicz and J.-L. Perret (UNM Paris and Current trends in biological physics DRIRE Rhône Alpes, Lyon) (24.11.2000) L. Matsson (Göteborg University) (23.11.2000)

Detecting gravitational waves: hopes and WORLDFIP Seminar expectations J.-W. Van Holten (NIKHEF and CERN) Développement d’applications WorldFIP en (30.11.2000) environnement temps réel P. Hoenig & P. Toureille (Silicomp Ingénierie) CMB evidence for symmetry-breaking during (19.01.2000) inflation? Réseau haute vitesse 25Mhz, WEB S. Sarkar (Oxford University) (07.12.2000) embarqué,Collaboration WorldFIP /Fieldbus Fondation (FF) et Capteurs Actionneurs Recent CMB data and the leptonic asymmetry Intelligents sur FF J. Lesgourgues (Annecy) (14.12.2000) R. Brun (CERN) P. Chatelet (Alstom) N. Fayard (Alstom) TIS Seminars J.-P. Froidevaux (Club WorldFIP, Clamart) P. G a ye t (C E RN ) Hearing day at CERN P. Kilidjean (Fisher-Rosemount) C. Schmid (CERN) (07.03.2000) A. Valdes (CERN) (24.05.2000)

392 Seminars & Colloquia Training Programme 2000

(Titles are in the language in which the course/seminar was given)

Academic Training Quality assurance – from quality control to TQM/ TQL D. Perrin, DP Counselling, Arconciel, CH Lecture Series for Postgraduate (3 lectures) Students Neutrino oscillations Introduction to particle accelerators L. Camilleri, CERN (5 lectures) E.J.N. Wilson, CERN (10 lectures)

Introduction to field theory An overview of string theory R. Kleiss, Univ. Nijmegen, NL (10 lectures) W. Lerche, CERN (3 lectures)

Introduction to QCD Energy concepts for the 21st Century B. Webber, CERN (10 lectures) P. Hjuler Jensen, RISOE, Roskildem, DK J.-P. Revol, CERN (5 lectures) Introduction to the Standard Model G. Ridolfi, CERN (10 lectures) CP violation in K-and B-Meson decays A. Buras, Tech. Univ. Munich, DE (5 lectures) Regular Lecture Programme Physics with next generation linear colliders Telling the truth with statistics K. Moenig, DESY, Zeuthen, DE (3 lectures) F. Ja m es, C ER N ( 5 l ec tu res) Introduction to circular and linear colliders Advanced materials for application to high J. Ellis, J. Gareyte and J.-P. Delahaye, CERN energy physics (5 lectures) B. Ilschner, EPFL, Lausanne, CH (5 lectures) Superconducting magnets Radiation damage in semiconducting devices, L. Rossi, Univ. Milan, IT (4 lectures) calorimeters and electronics J. Watts, Brunel Univ., Uxbridge, GB (5 lectures) XML: a new start for the Web

Reliability maintainability & safety in scientific- M. Goossens, CERN (4 lectures) technical projects R. Ansorge, RAMS-COM, Assling, DE Exploring object-oriented technologies (5 lectures) R. Ramos Pollan, CERN (3 lectures)

Training Programme 2000 399 Summer Student Lecture Programme LEP physics P. Janot, CERN (4 lectures) Introductions Beyond the Standard Model G. Giudice, CERN (3 lectures) Introduction to CERN and particle physics L. Maiani, CERN (2 lectures) CP violation T. Nakada, CERN (3 lectures) Radiation protection G. Stevenson, CERN (1 lecture) LHC physics F. Gianotti, CERN (3 lectures) Particle physics (for non-physics students) F. Close, CERN (4 lectures) Neutrino physics F. Dydak, CERN (4 lectures) Classic experiments M. Franklin, Harvard University, USA Heavy-ion physics (3 lectures) P. Sonderegger, CERN (2 lectures)

Ultra high vacuum technology Deep inelastic lepton scattering O. Gröbner, CERN (2 lectures) E. Gallo, DESY, Hamburg, DE (3 lectures)

Courses Introduction to cosmology E. Copeland, University of Sussex, GB Fundamental concepts of particle physics (3 lectures) R. Kleiss, Univ. Nijmegen, NL (6 lectures) Astroparticles Particle detectors C. Tao, Centre de Physique des Particules de T.S. Virdee, CERN (5 lectures) Marseille, FR (3 lectures)

Particle physics: the Standard Model Seminars C. Quigg, Fermilab, USA (8 lectures) Big experiments Trigger and data acquisition G. Rolandi, CERN (1 lecture) C. Gaspar, CERN (3 lectures) Other world labs From raw data to physics results L. Foà, Scuola Normale Superiore Pisa, IT R. Jacobsen, Lawrence Berkeley Laboratory, (1 lecture) USA (3 lectures) Advanced composite structures for physics Computing at CERN detectors and accelerators T. Cass, CERN (3 lectures) C. Hauviller, CERN (1 lecture)

Accelerators EMC – electromagnetic compatibility O. Brüning, CERN (5 lectures) F. Szoncso, CERN (2 lectures)

400 Training Programme 2000 ISOLDE physics overview The Java-based interface for the real time J. Aysto, CERN (1 lecture) presentation of the data in the distributed DAQ system Superconducting technology and cryogenics for N. Nethercote, University of Illinois, USA the LHC P. Lebrun, CERN (1 lecture) Efficiency of the third-level trigger of NA48 L. Fiorini, Scuola Normale Superiore, IT Superconducting cavities J. Tuckmantel, CERN (1 lecture) Looking Inside a Control System – Part I: Interfacing the supervision layer of a control Dreams of a finite theory system with a client server communication G. Veneziano, CERN (1 lecture) protocol B. Emir, Ecole Polytechnique Fédérale de Historic lecture Lausanne, CH L. Di Lella, CERN (1 lecture) Looking Inside a Control System – Part II: A method for implementing automatic tasks into Other a physical system (process layer) M. Sciamanna, Université de Mons-Hainaut, BE Introduction to workshops O. Ullaland, CERN (1 lecture) Analysis of single W production in ALEPH using an object-oriented computing language (C++) Discussion Sessions (10 sessions) M.V. Perez Reale, La Pampa National University Follow-up discussions on topics from the courses in Santa Rosa, AR and seminars CMStape S. Occhetti, Universitá del Piemonte Orientale, Student Sessions IT (Short presentations of 15 minutes by students on the work they carried out at CERN) Digital photogrammetry applied to the CMS detector Particle properties for Java analysis studio B. Alix, Ecole Supérieure des Géomètres et P. Hellwig, Universität Kaiserslautern, DE Topographes, FR

Measurement of triple gauge boson couplings MEDIPIX – Medical Imaging with PIxel- WWgamma and WWZ with the L3 detector at detectors and X-rays LEP B. Schatz, Universität Karlsruhe, GE M. Schneider, Université Louis Pasteur, FR

The ATLAS electromagnetic barrel calorimeter M. Bussmann, Ludwig-Maximilians Universität, DE

Unfolding detector effects for measurements of Bose–Einstein effects P. Olbrechts, Université Libre de Bruxelles, DE

Training Programme 2000 401 Language Training 1 individual course A. Fontbonne, CERN

Regular Courses English

French 1 writing course of 30 hours

Beginners 2 English for computing courses of 40 hours (18 courses of 54 to 60 hours)

3 specific courses for firemen of 20 hours Low-intermediate Paroles Sàrl, FR (15 courses of 54 to 60 hours)

3 self-paced courses Advanced-intermediate (12 courses of 30 to 40 hours) Learning how to learn a language (1 session of 5 × 0.5 day ) Advanced Goodfellow Formations, FR (3 courses of 30 hours) Paroles Sàrl, FR

Management and Communication English

Beginners Management (6 courses of 60 hours) Techniques de communication - 1 / Intermediate Communication techniques - 1 (17 courses of 40 hours) S. Datta Cockerill, CERN (1 session of 3 days)

Advanced Le fonctionnement du CERN / How CERN is (1 course of 40 hours) organized Paroles Sàrl, FR Experts, CERN (3 sessions of 2 days)

Introduction au management / Introduction to Special Courses management T. Bastiaans, Indoor Outdoor Management French Training bv, NL; S. Datta Cockerill, CERN (2 sessions of 3 days) 1 writing course of 27 hours Paroles Sàrl, FR Techniques de communication - 2 / Communication techniques - 2 3 self-paced courses M. Hawker and R. Winden, CRAC, GB (1 session M. Laurent, CERN of 3 days)

402 Training Programme 2000 Managing by project Gérer un projet / Project management B. Denis, CERN (1 session of 3 days, 1 session of G. Vallet, Highware, GB (3 sessions of 3 days) 2 days) Planification et gestion des coûts / Project Animer une équipe / Running a team scheduling and costing R. Phillips, Ashridge Management College, GB; G. Vallet, Highware, GB (2 sessions of 3 days) F. Fabre, CERN (1 session of 3 days, 1 session of 4 days) Gestion de la qualité / Quality management G. Vallet, Highware, GB (1 session of 3 days) Techniques de communication - 3 / Communication techniques - 3 Gestion des risques / Risk management G. Vallet, Highware, GB (1 session of 2 days) R. Weisz, Aix Consulting Group, FR (1 session of 2 days) Communication Le leadership / Leadership R. Weisz, Aix Consulting Group, FR (1 session of Communiquer efficacement 2 days) P. Artigues, FR (2 sessions of 4 days)

Women in management Communicating effectively S. Vinnicombe and S. Kumra, Cranfield S. Datta Cockerill, CERN (1 session of 4 days) University, GB (1 session of 2 days) Les techniques de communication dans une Gérer une unité au CERN: être un manager / équipe Managing a CERN unit: to be a manager P. Artigues, FR (1 session of 2 days) B. Overlaet, Promind Consulting, BE; R. Phillips, Ashridge Management College, GB; Agir sur les processus relationnels R. Weisz, Aix Consulting Group, FR; F. Fabre, D. Rolland, Aix Consulting Group, FR (1 session CERN (3 sessions of 6 days) of 3 days)

Développement des aptitudes à la supervision Interacting with people R. Weisz, Aix Consulting Group, FR (1 session of P. Artigues, FR; B. Overlaet, Promind 2 days) Consulting, BE (1 session of 4 days)

Travailler efficacement en équipe Atelier d’équipe / Team workshop D. Mullen, Performance Support, FR (1 session P. Artigues, FR (1 session of 2 days) of 1 day)

Appréciation des performances La gestion du stress F. Fabre, CERN (5 sessions of 3 days, 1 session M. Michal, Leadership 2000, CH (2 sessions of of 1 day) 2 days)

Performance appraisal Stress management R. Phillips, Ashridge Management College, GB; M. Michal, Leadership 2000, CH (3 sessions of L. Orr-Easo, CERN (4 sessions of 3 days) 2 days)

Training Programme 2000 403 Harcèlement sexuel au travail An overview of the Java programming language V. Ducret, CH (1 session of 1 day) OSYX, FR (2 session of 0.5 day)

Techniques d’exposé et de présentations The Java programming language, level 1 S. Courau de Closets, C&CIE, FR; P. Duhoux, OSYX, FR (3 sessions of 2 days) Diacofor, FR (2 sessions of 2 days, 1 session of 3 days) The Java programming language, level 2 OSYX, FR (3 sessions of 3 days) Making presentations K.M. Storr, CERN (1 session of 2 days, 1 session Programming for the Web using Java of 3 days) OSYX, FR (1 session of 2 days)

Animer ou participer à une réunion de travail Hands-on object-oriented design and P. Duhoux, Diacofor, FR; D. Zenou, C&CIE, FR programming with Java (2 sessions of 2 days) J. Deacon, GB (1 session of 3 days)

Chairing or participating in meetings JFC and the swing architecture K.M. Storr, CERN (1 session of 2 days) OSYX, FR (1 session of 3 days)

Négociation UNIX pour non-programmeurs B. Overlaet, Promind Consulting, BE (1 session OSYX, FR (1 session of 3 days) of 2 days)

Object-oriented analysis and design Negotiating skills B. Overlaet, Promind Consulting, BE (1 session J. Deacon, GB (1 session of 4 days) of 2 days) Objectivity/DB for C++ developers Lecture rapide Objectivity Europe, NL (1 session of 3 days) I. Chevalier, Centor, FR (1 session of 2 days) Hands-on object-oriented analysis, design & Création de posters programming with C++ P. Duhoux, Diacofor, FR (1 session of 2 days) J. Deacon, GB (1 session of 5 days)

The CERN Engineering Data Management Technical Training System for advanced users D. Widegren, CERN (2 sessions of 2 days)

Software and Systems Technologies Introduction to the CERN Engineering Data Management System Introduction to C programming D. Widegren, CERN (6 sessions of 1 day) OSYX, FR (1 session of 3 days) Oracle8 and Oracle8i: new features for Introduction to software engineering developers J. Deacon, GB (1 session of 2 days) Oracle, CH (2 sessions of 5 days)

404 Training Programme 2000 Oracle8i for application developers Advanced aspects of the C language Oracle, CH (1 session of 5 days) OSYX, FR (1 session of 2 days)

Introduction to Oracle SQL and PL/SQL Oracle, CH (1 session of 5 days) Electronics Design

Develop PL/SQL program units LabView base 1 Oracle, CH (1 session of 3 days) National Instruments, CH (2 sessions of 3 days)

Oracle application server: develop Web-based LabView basics 1 applications with PL/SQL National Instruments, CH (1 session of 3 days) Oracle, CH (1 session of 2 days) LabView Hands-on Introduction to CORBA National Instruments, CH (2 sessions of 0.5 day) OSYX, FR (1 session of 3 days) LabView Connectivity C++ programming level 2 – traps & pitfalls National Instruments, CH (1 session of 1 day) J. Deacon, GB (1 session of 4 days) LabView CVI Hands-on C++ for particle physicists National Instruments, CH (1 session of 0.5 day) P. Kunz, USA (2 sessions of 6 × 3 hours)

BridgeView Introduction to XML National Instruments, CH (1 session of 3 days) OSYX, FR (3 sessions of 2 days)

Comprehensive VHDL for EPLD/FPGA design Hands-on object-oriented design and Doulos, GB (3 sessions of 5 days) programming with Java J. Deacon, GB (1 session of 3 days) PCAD PCB – débutants

Design patterns CONNEXE, CH (2 sessions of 3 days) J. Deacon, GB (2 sessions of 2 days) PCAD Schémas – débutants Introduction to PERL 5 CONNEXE, CH (1 session of 2 days) OSYX, FR (1 session of 2 days) CANbus Advanced aspects of PERL 5 NSI, FR (1 session of 1 day) OSYX, FR (1 session of 1 day) CANopen Introduction to databases NSI, FR (1 session of 2 days) J. Deacon, GB (2 sessions of 2 days) Pratique de l’analyse d’intégrité des signaux à Advanced and modern databases l’aide de SPECCTRAQuest J. Deacon, GB (1 session of 2 days) J.M. Sainson, CERN (1 session of 2 days)

Training Programme 2000 405 Materials and Mechanical Design Word CIP, FR (2 sessions of 4 days) AutoCAD 2D – niveau 1 Cad’s Cool, CH (2 sessions of 4 days) Nouveautés de Word CIP, FR (1 session of 1.5 day) AutoCAD 2D – level 1 Cad’s Cool, CH (1 session of 4 days) Word: importer et manipuler des images AutoCAD 2D – niveau 2 CIP, FR (12 sessions of 1 day) Cad’s Cool, CH (1 session of 5 days) EXCEL AutoCAD 3D CIP, FR (6 sessions of 4 days) Cad’s Cool, CH (2 sessions of 2.5 days)

Nouveautés d’EXCEL AutoCAD mechanical desktop CIP, FR (1 session of 1.5 days) Cad’s Cool, CH (1 session of 10 days)

Cotation selon les normes ISO FileMaker ENS, FR (3 sessions of 2 days) CIP, FR (2 sessions of 4 days)

Cryogénie (Introduction) Introduction à Netscape Mail CNRS, FR (2 sessions of 5 days) CIP, FR (1 session of 0.5 day)

Introduction to ANSYS 5.4 Publier sur le Web ANCO, FR (1 session of 3 days) CIP, FR (7 sessions of 1.5 day) EUCLID tôlerie Matra, FR (1 session of 2 days) ACCESS niveau 1 IT Academy, CH (1 session of 2 days) Eurocode 3, calcul des structures en acier CAST, FR (2 sessions of 4 days) MS-Project 1er niveau CIP, FR (2 sessions of 2 days) Office Software and Administration MS-Project 2e niveau Introduction à Windows 95 au CERN CIP, FR (1 session of 2 days) CIP, FR (1 session of 2 days) Initiation au WWW Premiers pas avec votre PC au CERN CIP, FR (2 sessions of 1.5 day) CIP, FR (2 sessions of 2 days)

Contract follow-up Introduction à PowerPoint CIP, FR (3 sessions of 1 day) R. Bray, CERN (19 sessions of 0.5 day)

Introduction to PowerPoint Utilisation de Visual Basic avec EXCEL 7.0/97 K.M. Storr, CERN (1 session of 1 day) IT Academy, CH (1 session of 2 days)

406 Training Programme 2000 Safety Radiation effects on electronic components and systems for LHC Sécurité dans les installations cryogéniques Organized by P. Jarron, CERN (1 session of P. Gianese, FR (2 sessions of 2 days) 3 days)

Sécurité électrique HT/BT – Recyclage StarCD G. Salomon, CERN (7 sessions of 0.5 day) Computational Dynamics, GB (1 session of 3.5 days) Sécurité de travail avec laser G. Roubaud, CERN (1 session of 1 day) Use of Simplorer simulator Applied Magnetics, CH (1 session of 3 days) Gaz inflammables 1 B. Nuttall and A. Smith, CERN (1 session of Windows 2000 1 day) R. Sanders, CH (2 sessions of 1.5 days)

Sécurité dans les installations cryogéniques Architecture d’automatisme CRBT/CNRS, FR (3 sessions of 1 day) Schneider Formation, FR (1 session of 2 days)

Habilitation électrique: électriciens network Programmation TSX Premium 1 AIF, FR (1 session of 2 days) Schneider Formation, FR (1 session of 4 days)

Flammable gas detection Programmation TSX Premium 2 Loss Prevention Council, GB (1 session of 2 days) Schneider Formation, FR (1 session of 4 days)

Special courses Apprenticeships

ATLAS DAQ-1 back-end subsystem training Number of apprentices from September 1999 to Organized by R. Jones, CERN (1 session of August 2000 1 day) 1st 2nd 3rd 4th Profession Total year year year year PVSS Laborant en 333312 ETM, AT (1 session of 5 days) Physique Electronicien444416 Employé de PS hands-on object-oriented design and 11– 2 commerce programming with Java Assistant en J. Deacon, GB (2 sessions of 4 days) information 1–– 1 documentaire Introduction to Rational ROSE Rational Software, CH (1 session of 2 days) The four ‘Electroniciens’ and the three ‘Laborants en Physique’ who completed their Rational SODA for Word apprenticeships in 2000 obtained the Swiss Rational Software, CH (1 session of 1 day) ‘Certificat Fédéral de Capacité’ (CFC).

Training Programme 2000 407

CERN Schools

Accelerator Schools Basic concepts I, II H. Henke, TU Berlin

RF Engineering, Lufthansa Training Centre Cavity design procedures Seeheim, Germany, 8–16 May 2000 E. Jensen, CERN RF engineering is a key technology in accelerators and for the fourth time in recent High-frequency non-ferrite cavities years the CERN Accelerator School has provided J. LeDuff, LAL a course on this topic. This time it was organized with the help of GSI Darmstadt at the Lufthansa Choosing the RF frequency Training Centre in Seeheim from the 8th to 16th W. Pirkl, CERN May 2000. It was attended by 13 students from CERN, 19 from Germany and 29 from elsewhere H-Type linacs including 6 scholarship students funded by U. Ratzinger, GSI UNESCO. RFQ A. Schempp, Frankfurt University Lectures Cavities with a swing Low level systems I, II A. Schnase, FZ Jülich GmbH P. Baudrenghien, CERN Cyclotron cavities Superconducting cavities P. Sigg, PSI G. Bisoffi, INFN-LNL Review of Theory I, II, III Design of ring RF systems T. Weiland, TU-Darmstadt D. Boussard, CERN Cavity construction techniques RF power sources I, II High power transmission W. Wuensch, CERN R.G. Carter, Lancaster University

Servo control Tutorials A. Gamp, DESY Microwave measurements RF gymnastics F. Caspers, CERN R. Garoby, CERN G. Hutter, GSI

CERN Schools 393 A and D controls Lectures I. Reyzl, DESY Basic phase space S. Simrock, DESY A. Lebedev, JINR

Linear accelerators Linear beam dynamics and beyond A. Richter and H-D. Graef, TU-Darmstadt E. Perevedentsev, Novosibirsk M. Vretenar, CERN Quality limitation for hadron beams Mode coupling instabilities J. Gareyte, CERN Seminars Quality limits for electron rings Two beams as an RF power source T. Kasuga, KEK R. Corsini, CERN Review of luminosity limitations Radioactive beam accelerators S. Kurokawa, KEK A. Muller, INP Review of cooling Stochastic cooling and related RF components V. Parkhomchuk, BINP

F. No l d en , G S I Wake fields, impedances G. Stupakov, SLAC Superconductivity V. Palmieri, INFN-LNL Intrabeam scattering J. Struckmeier, GSI Medical accelerators Residual gas and ion effects E. Pedroni, PSI H. Fukuma, KEK

Emittance preservation in proton rings Joint CERN–Japan–Russian–JINR–USA Advanced Accelerator School on High Quality Luminosity lifetime and halo effects Beams (JAS’2000), Russia, 1–14 July 2000 F. Willeke, DESY

Every second year the CERN Accelerator School, Emittance preservation in linac together with the US Particle Accelerator School M. Minty, DESY and their counterparts in Japan and Russia, organize a joint school at a location which Beam–beam interaction (basic) alternates between the four geographical regions Beam–beam effects involved. This year and for the first time Russia J. Seeman, SLAC was the host for the course. They chose to hold Vlasov equation and Landau damping the course on a river steamer plying between St. Transverse instabilities, head–tail instabilities Petersburg and Dubna. The course, entitled D. Pestrikov, BINP ‘High Quality Beams’ took place from the 1st to 14th July 2000 and it attracted 63 students Beam loading issues in ring including 3 from CERN, 7 from Europe, 4 from K. Akai, KEK Asia, 46 from Russia and 5 from the USA; of these 5 were funded by UNESCO. The 32 Longitudinal instability lecturers came from all four participating regions. L. Palumbo, University of Rome

394 CERN Schools HOM compensation Tutorials T. Kageyama, KEK Space charge Beam–beam effects in linear colliders S. Machida, KEK & N. Vinokurov, BINP K. Yokoya, KEK Insertion and crossing region design Polarized electron beams H.-U. Wienands, SLAC & P. Beloshitsky, CERN Polarized proton beams Y. Shatunov, BINP Beam quality control for linear colliders F. Zimmermann, CERN & P. Logachev, BINP High brightness electron storage rings J. Murphy, BNL Introduction to Accelerator Physics Course, Beam feedback systems Loutraki, Greece, 2–13 October 2000 M. Tobiyama, KEK The two-year cycle of Basic and Intermediate Structure of elementary particle theory Accelerator Physics commenced at the basic level D. Shirkov, JINR with a course held in Loutraki, some 100 km west of Athens, from 2–13 October 2000. The course Status report of JINR activities included a visit to I.A.S.A. at the nearby V. Zhabitsky, JINR University of Athens. CERN sent 36 of the 80 participants and the next largest participation Summary of the course came from Germany who sent 15. I. Meshkov, JINR Hill’s equation Transverse optics Seminars Transfer lines Future colliders Resonances E. Keil, CERN S. Baird, CERN

High power DC electron accelerators Electrostatic accelerators R. Salimov, BINP H. Grunder, CEBAS & I. Khubeis Al Balqa Applied University Electron medical accelerators E. Tanabe, AET Japan Inc. Diagnostics I, II H. Koziol, CERN Muon colliders A. Skrinsky, INP E.M. theory Relativity Accelerators recuperators for FEL and other A. Lahanas, University of Athens applications N. Vinokurov, BINP Longitudinal dynamics I, II Antihydrogen and positronium generation Transition I. Meshkov, JINR J. Le Duff, LAL

Polarized electron sources Beam cooling T. Nakanishi, Nagoya University D. Mohl, CERN

CERN Schools 395 Control loops in accelerators Seminars F. Ped e rs en , CE RN Archeometry Linacs Prof. Assimakoupolos, University of Ionnina N. Pichoff, CEA-Saclay Project management G. Bachy, CERN Instabilities: Linacs A. Pisent, LNL-INFN Case study: ELFE G. Geschonke, CERN Physics of Accelerators C. Prior, RAL Life and work of N. Christofilos, who is credited with the discovery of strong focusing RF hardware H. Grunder, CEBAF G. Geschonke, CERN Applications of accelerators Magnets Y. Jongen, IBA S. Russenschuck, CERN The applied physics program Space charge M. Pantos, Daresbury Laboratory Instabilities: Rings Microtrons K.-H. Schindl, CERN E. Stiliaris, IASA Electron sources C. Travier, CEA/DAPNIA/SEA CAS Accelerator Seminar

Open Sesame In addition to the above courses CAS organized G. Voss, DESY the annual John Adams Memorial Lecture.

Synchrotrons The TESLA Test Facility and the first FEL for the E. Weihreter, BESSY vacuum ultraviolet Jörg Rossbach, DESY Putting it all together E. Wilson, CERN School of Computing

Tutorials The 23rd CERN School of Computing took place at the Hotel Golden Coast, Marathon, Greece Synchrotron radiation from 17–30 September 2000. The School was L. Rivkin, PSI organized in collaboration with the Institute of E. Weihreter, BESSY Nuclear Physics NCSR ‘Demokritos’, Athens, Greece. Linacs M. Vretenar, CERN Seventeen lecturers, of whom six were from N. Pichoff, CEA-Saclay CERN, one from Japan, four from the USA and six from Europe, were invited to give courses at Muon colliders & neutrino sources the School. One of the six lecturers from CERN E. Keil & C. Johnson, CERN was also enrolled as a student. There were also

396 CERN Schools four assistant lecturers. Seventy-four students 2000 European School of High- (coming from 46 institutes, 22 countries and of Energy Physics 24 nationalities) attended the School, 13 of whom were funded by UNESCO; of these 13, six also The eighth European School of High-Energy received funding for their travel. Physics took place in Caramulo, Portugal, from 20 August–2 September 2000. It was attended by The programme of the School was organized 101 students representing 29 different countries, around three themes: Storage and Software mainly CERN and JINR Member States, together with four Portuguese ‘listeners’. The Systems for Data Analysis, OO Design and accommodation was in twin rooms with students Implementation, and Distributed Computing. It of different nationalities, and as far as possible consisted of 41 hours of lectures (including three from Eastern and Western countries, sharing the evening lectures) and 19 hours of exercises. same room. This mixing of nationalities is an important element of the school helping in Three evening lectures took place. establishing contacts and often forging long- lasting friendships among the students. Application services provision The main lecture courses, designed to give young M. Griera I Fisa, European Commission experimental high-energy physics doctoral students a sound basis in theory, were as follows: An introduction to the history of Greek vineyards

A. Spyropoulous Field theory and the Standard Model R. Kleiss, Nijmegen University High precision dating with carbon-14 as a tool for Beyond the Standard Model monitoring cultural and environmental events in D. Kazakov, JINR, Dubna prehistory

Y. Maniatis QCD V. Braun, Regensburg University Practical exercises were an important part of the Flavour physics programme and required a complex computing G. Branco, IST, Lisbon infrastructure. Neutrinos Computing and peripheral equipment was A. De Rújula, CERN provided by and via CERN. Equipment lent by various computer manufacturers was delivered to Heavy ions CERN where it was set up, tested, dismantled and J. Dias de Deus, IST Lisbon shipped to Marathon. Our Greek colleagues Cosmology and astrophysics provided the network connection from Marathon, M. Shaposhnikov, Lausanne University handled the details of the Web page, as well as technical and secretariat assistance. The exercises A number of more specialized lectures were also were very well prepared and very well attended. given, including reviews of the physics programmes of CERN and JINR. An evening Setting up the complex computing facility, even lecture was also presented by C. Jarlskog, entitled if only needed for a short time, needed close ‘How to win a Nobel Prize’. In total, 32 formal collaboration and was widely appreciated. lectures, each of 90 minutes duration were given.

CERN Schools 397 The lectures were reinforced by discussion given by UNESCO and INTAS contributing sessions, also of 90 minutes duration, held most towards the attendance of students from countries days during the school. Each discussion group of which otherwise would not have been able to about 15–20 students was guided by a discussion send their students to the School. Some local leader. The School was sponsored by CERN and support was also made available. JINR, Dubna. Substantial contributions were

398 CERN Schools Distinguished Visitors in 2000

January February

5 Dr Catherine Cesarsky 9 H.E. Mr Sergio Marchi Director-General, European Southern Ambassador, Permanent Representative of Observatory (ESO) Canada to the Office of the United Nations and other International Organizations in 18 Professor Reijo Vihko Geneva President of the Academy of Finland 15 Dr Szabolcz Lanyi President of the National Agency for 19 Professor Ya’akov Ziv Science, Technology and Innovation of President of the Israel Academy of Sciences Romania and Humanities

16 Dr Michael Scholtz 20 Dr Morten Dæhlen Executive Director for Health Technology Director for Natural Science and Technology, and Pharmaceuticals, World Health Norwegian Research Council Organization

26 Professor Cornelis W.P.M. Blom 17 Ambassadors to CERN Rector Magnificus, Nijmegen University, Netherlands Mr Dimiter Gantchev Minister Plenipotentiary, Bulgaria H.E. Mr François Nordmann H. E. Mr Zonghuai Qiao Ambassador, Permanent Representative of Ambassador, China Switzerland to the International Organizations in Geneva and Permanent H. E. Mr Henrik Rée Iversen Observer to the Office of the United Nations Ambassador, Denmark in Geneva H. E. Mr Pekka Huhtaniemi Ambassador, Finland 27 Mr Philippe Busquin Commissioner for Research, European H. E. Mr Walter Lewalter Commission Ambassador, Germany

Professor Lu Yongxiang Mrs Dimitris Karaitidis President of the Chinese Academy of Greece Sciences

Distinguished Visitors in 2000 409 Mrs Vassilikigounaris 17 Professor Kåre Bremer First Secretary, Greece Secretary-General of the Swedish Natural Science Research Council Mr Ferenc Bösenbacher Chargé d’affaires, Hungary 20 Mr Matan Vilnai H. E. Mr Hans J. Heinemann Minister of Science, Culture and Sport, Israel Ambassador, Netherlands

H. E. Mr Kalman Petocz Ambassador, Slovakia April

H. E. Mr François Nordmann 4 Professor Alan Bunner Ambassador, Switzerland Science Programme Director, NASA Headquarters, Washington D.C., USA H. E. Mr Simon Fuller Ambassador, United Kingdom 6 The State Council of Geneva and the State Council of Fribourg, Switzerland 21 Dr Jean Audouze Director, Palais de la Découverte, Paris 26 Dr Vladislav Stepine Director of the Institute of Philosophy of the 22 Professor Hans Wigzell Moscow Academy of Sciences, Russian President of Karolinska Institutet, Sweden Federation Dr Mario Annoni Director of Education, State Councillor, 28 H.E. Mr Munir Akram Canton of Berne Ambassador, Permanent Representative of the Islamic Republic of Pakistan to the Office Professor Chr. Schäublin of the United Nations and Specialized Rector of the Univesity of Bern Institutions in Geneva

23 Mr Antoine Frassetto H. E. Mr Christopher Hulse Her Majesty’s Ambassador to Switzerland Consul-General of France in Geneva

March May

5 Ambassadors to CERN 2 Professor Félix Yndurain Director-General of CIEMAT, Spain H. E. Mr Harald Kreid Ambassador, Permanent Representative, 10 H.E. Mr Eduard Kukan Austria Minister of Foreign Affairs, Slovak Republic H.E. Mr Miroslav Somol Ambassador, Permanent Representative, 15 H. E. Mr Nguyen Quy Binh Czech Republic Ambassador, Permanent Representative of the Socialist Republic of Vietnam to the H. E. Mr Luis Gallegos Chiriboga Office of the United Nations and other Ambassador, Permanent Representative, International Organizations in Geneva Ecuador

410 Distinguished Visitors in 2000 H. E. Mr Philippe Petit 31 Mr Charles Butcher Ambassador, Permanent Representative, Chairman of The Lazy Eight Foundation, France Colorado, USA

H. E. Mrs Savitri Kunadi Ambassador, Permanent Representative, India June

H. E. Mr David Peleg 2 Mr István Wimmer Ambassador, Permanent Representative, Secretary-General of the Federation of Israel Hungarian Employers and Industrialists

H. E. Mr Koichi Haraguchi Professor Colin Jones Ambassador, Permanent Representative, Chair of the Board of Management of Japan TRIUMF, Canada H. E. Mr Alvaro de Mendoça e Moura Ambassador, Permanent Representative, 3 Dr Gudrun Graf Portugal Minister, Deputy Permanent Representative of Austria to the United Nations and Mr Antonio Luis Bullón Camarasa Specialized Institutions in Geneva Minister, Deputy Permanent Representative, Spain 6 Dr Klaus Schwab H. E. Mr Murat Sungar President of the World Economic Forum, Ambassador, Permanent Representative, Switzerland Turkey 7 Dr Catherine Bréchignac 11 Mr Michel Héon Director-General, CNRS, France Inspector-General, National Education Ministry, France 15 Mr John Love Head of Administration, PPARC, United 15 Dr Lorenzo Dellai Kingdom President of the Provincia Autonoma di Trento, Italy 19 Professor Henry Minzberg Faculty of Management, McGill University, 17 Rabbi Shlomo Benizri Canada and INSEAD, France Minister of Health, Israel 21 Professor Dimitar Balarew 18 H. R. H. Princess Maha Chakri Sirindhorn Deputy Minister of Education and Science, Thailand Bulgaria

20 Mr Mario Bologna 23 Professor Harry Voorma Consul-General of Italy, Lyons, France Rector of Utrecht University, Netherlands

30 Mr Keith Levinson 26 H. E. Mr Wen Jiabao Director, Business in Europe, Department of Vice-Premier of the State Council of the Trade and Industry (DTI), United Kingdom People’s Republic of China

Distinguished Visitors in 2000 411 July 13 Mr Susumu Yoda Commissioner, Japanese Atomic Energy Commission 10 Professor Enric Banda

Secretary-General of the European Science 15 Professor Hubert Markl Foundation, Strasbourg, France President of the Max Planck Society, Germany 11 Mr Paul Bennett Professor Atta-ur-Rhaman Counsellor, Deputy Permanent Minister of Science and Technology, Representative (WTO) for Ireland to the Pakistan United Nations and Specialized Insitutions in Geneva 16 Mr Bill Richardson Secretary of Energy, United States of 14 Dr José Traest America Secretary-General, Fonds voor Wetenschappelijk Onderzoek (FWO), and 26 Mrs Véronique Debisschop Rectors of Flemish Universities, Belgium Regional Delegate for the Rhône-Alpes, CNRS, France

August 29 Hermann von Helmholtz Association of German Research Centres, Germany

9Mrs Catherine Stuck Professor Themistoklis Xanthopoylos Rector, National Technical University, Head of Human Resources, ESRF, Grenoble, Athens, Greece France

29 Mr Hervé Gaymard October Member of the French Parliament, President of the General Council of the Department of 9 LEP Celebrations Savoy, France Mrs Anna Birules Minister for Science and Technology, Spain

September Mrs Agneta Bladh State Secretary for Education and Science, 8 Professor Dewi M. Lewis CPhys FinstP Sweden Vice-President, Physics, Nycomed Mr Philippe Busquin Amersham plc Commissioner for Research, European Commission

11 Dr Ishfaq Ahmad Mrs Edelgard Bulmahn Chairman of the Pakistan Atomic Energy Minister for Education and Research, Commission Germany

412 Distinguished Visitors in 2000 Professor Dimitris Deniozos Lord Sainsbury of Turville General Secretary for Research and Minister for Science, United Kingdom Technology, Greece Mr Roger-Gérard Schwartzenberg Professor Dimitar Dimitrov Minister for Research, France Minister for Education and Science, Bulgaria Professor Andrezej Wiszniewski Mr Lubomir Fogas Minister for Science, Poland Deputy Prime Minister, Slovak Republic Dr Keisuke Yoshio Mr Safter Gaydali Director, International Scientific Affairs State Minister, Turkey Division, Monbusho, Japan

H. E. Mr Hans J. Heinemann Professor Ostensio Zecchino Ambassador, Netherlands Minister of University and Scientific and Mr Vilho Hirvi Technological Research, Italy General Secretary, Minister of Education, Also present: Finland Professor Martinus J.G. Veltman Dr Miroslav Janecek 1999 Nobel Laureate in Physics, Professor Deputy Chairman of the Research and Emeritus, University of Michigan Development Council, Czech Republic

Mr Mikhail Kirpichnikov 12 Mr René Trégouët Vice-Prime Minister for Science, Russian Senator of the Department of the Rhône, Federation France, Rapporteur of the Parliamentary Office for evaluation of scientific and Professor Wolfgang Kummer technological options with respect to the role Former President of CERN Council of very large experiments, Special H. E. Mrs Savitri Kunadi Rapporteur of the Senate Finance Committee Ambassador, India on funding for parliamentary research into the evaluation of scientific and technological Mr Knud Larsen options Permanant Secretary, Ministry of Research, Denmark 13 H.E. Mr Yevhen Bersheda H. E. Mr Jean-Marie Noirfalisse Ambassador to Switzerland for the Ukraine Ambassador, Belgium 16 H. E. Mr Rudolf Joó Dr John O’Fallon Ambassador Extraordinary and Director, Division of High Energy Physics, Plenipotentiary, Permanent Representative of US Department of Energy, USA Hungary to the Office of the United Nations Mrs Randi Oeverland and other International Organizations in State Secretary for Education, Norway Geneva

Mr Adolf Ogi 17 Mrs Malgorzata Kozlowska President of the Swiss Confederation Undersecretary of State, State Committee for Mr Jozsef Palinkas Scientific Research, Poland on the occasion State Secretary for Education, Hungary of the Poland at CERN exhibition

Distinguished Visitors in 2000 413 20 Mr Anil Kakodkar Director, Bhabha Atomic Research Centre (BARC), Chairman-Designate of the Atomic Energy Commission; Secretary, Department of Atomic Energy, India 9Dr Klaus Zyla Leader of the Austrian Trade Delegation for 23 Mrs Marie-Gabrielle Philippe Switzerland and Liechtenstein Sub-Prefect of Gex, France Mr Philippe Busquin Commissioner for Research, European 26 Mr Ramón Marimón Commission Secretary of State, Ministry of Science and Technology, Spain Mr Vladimir Chmelar Chairman of the Board of Directors, General Manager of Tesla SEZAM, Czech Republic

November Dr Catherine Cesarsky Director-General, European Southern 1 Mr David Roberts Observatory (ESO) Director of Trade and Investment for Switzerland and Liechtenstein, British Mr Christian Foldberg Rovsing Embassy, Berne Member of the Committee on Industry, External Trade, Research and Energy, 5 Mr D. Josep Varela i Serra European Parliament Senator, Member of the Catalan Parliamentary Group, Spain 14 Sir David Wright Chief Executive of British Trade 7 Members of the House of Commons Select International on the occasion of the Britain at Committee on Science and Technology, UK CERN exhibition

Mr Tam Dalyell MP 20 Mr Carmel Vernia Dr Brian Iddon MP Chief Scientist, Ministry of Industry, Israel

Dr Ashok Kumar MP 22 H. E. Mr Yaakov Levy The Rev. Martin Smyth MP Ambassador, Permanent Representative of Israel to the Office of the United Nations and Professor David Saxon Specialized Institutions in Geneva PPARC, Member of PPARC Council and Chairman of the Public Understanding of Science Panel

414 Distinguished Visitors in 2000