NEWS RHIC begins smashing nuclei

Gold at STAR - side view of a collision of two 30 GeV/nucleon gold End view in the STAR detector of the same collision looking along beams in the STAR detector at the Relativistic Heavy Ion Collider at the direction of the colliding beams. Approximately 1000 tracks Brookhaven. were recorded in this event

On Monday 12 June a new high-energy laboratory director for RHIC. It was a proud rings filled, the ions will be whipped to machine made its stage debut as operators in moment for Ozaki, who returned to 70 GeV/nucleon. With stable beams coasting the main control room of Brookhaven's Brookhaven from Japan to oversee the con­ around the rings, the nuclei collide head-on, Relativistic Heavy Ion Collider (RHIC) finally struction and commissioning of this eventually at the rate of tens of thousands of declared victory over their stubborn beams. challenging machine. collisions per second. Several weeks before, Derek Lowenstein, The high temperatures and densities Principal RHIC components were manufac­ chairman of the laboratory's collider-acceler­ achieved in the RHIC collisions should, for a tured by industry, in some cases through ator department, had described repeated fleeting moment, allow the quarks and gluons co-operative ventures that transferred tech­ attempts to get stable beams of gold ions to roam in a soup-like plasma - a state of nology developed at Brookhaven to private circulating in RHIC's two 3.8 km rings as "like matter that is believed to have last existed industry. learning to drive at the Indy 500!". millionths of a second after the Big Bang. The RHIC tunnel is filled with 1740 super­ With beams finally circulating in the col­ Information from RHIC experiments will round conducting magnets in two rings, which bend lider's twin rings on a collision course at an out the quark-gluon plasma knowledge gained and focus the particles. Dipole and quadru- energy of 30 GeV per nucléon, the waiting through experiments using nuclear beams at pole magnets were built by the Northrop- STAR detector captured the first spectacular lower energies at CERN's SPS synchrotron. Grumman Corporation on Long Island, and images of particles streaming from a head-on RHIC construction began in 1991, and the sextupole magnets were built by Everson collision point, showing an impressive shower project was completed last year, when all Electric, in Bethlehem, Pennsylvania. of about 1000 tracks, but this was just a parts of the machine were initially tested and Brookhaven built the corrector magnets and foretaste of bigger things to come. Soon, operated as a complete system, but just short other special magnets. collisions were also seen by the BRAHMS, of physics operation. Construction and com­ The RHIC tunnel configuration provides for PHENIX and PHOBOS detectors. missioning costs totalled $600 million. six areas where the circulating beams cross The result is great news for the thousands of Nuclei destined for RHIC originate in the and where collisions take place. Four areas physicists, engineers and support staff who laboratory's Tandem Van de Graaff, proceed now contain detectors - two large ones, STAR have been working since 1991 to get RHIC up into the booster and then travel on to the and PHENIX, and two smaller assemblies, and running, and for physicists everywhere venerable Alternating Gradient Synchrotron PHOBOS and BRAHMS. All together, close to who have been anticipating RHIC's debut. (AGS), which first came into operation in 1000 scientists from 90 research institutions "These are the most spectacular subatomic 1960.The AGS injects nuclear beams into representing 19 countries are working on RHIC collisions ever witnessed by humankind, RHIC for experiments. experiments. representing the culmination of many years of For RHIC, bunches of nuclei are injected For more information and to follow RHIC's hard work," said Satoshi Ozaki, associate into each of the two rings.Then, with both progress, visit "http://www.rhic.bnl.gov/".

CERN Courier July/August 2000 5 NEWS

Unity in diversity - DESY turns 40 Bjorn Wiik Research Project The World Laboratory Bjorn Wiik Research Project/created in honour of the late Bjorn Wiik, awards scholarships to young scientists from developing countries to enable them to pursue research and training at DESY in particle or accelerator physics, application of synchrotron radiation and high-performance computing. Birthday party - the central area of DESY's Mikhail Yurkov of Russia, who was one of VIP preview of the DESY exhibition. Left to EXPO exhibition, Light for the New the first winners of a Wiik scholarship, in right: Polish Science Minister Andrzéj Millennium, which was the venue for the recognition of his pioneering work on the Wischniewsky DESY director-general celebrations marking the 40th anniversary FEL, was one of the keynote young speakers Albrecht Wagner, Minister Edelgard Bulmahn of the Hamburg laboratory on 23 May this at the DESY anniversary event. and DESY director for synchrotron radiation year. (DESY.) research Jochen Schneider. (DESY.)

On 18 December 1959 the state contract was Gerhard Schroeder were conveyed by Edelgard believes, the project of the future. "I admire signed and DESY was born. However, like Bulmahn, Federal Minister for Education and the foresight and courage of Bjorn Wiik in some monarchs, the German DESY laboratory Research. She commended the "diversity" - putting this project together," she said. in Hamburg chose a different date for its the symbiosis of different research areas at Five young physicists, representative of the official birthday. On 23 May, 2400 people took DESY - a theme echoed by Hamburg deputy diversity of nationalities under DESY's roof, their seats in a balloon-filled marquee to mayor Krista Sager, who stressed the benefit presented an overview of research at DESY, celebrate DESY's 40th birthday, with the of doing applied as well as basic research. focusing on the unique HERA electron-proton theme "Unity in diversity". Sager also acknowledged the impact of DESY collider and the Free Electron Laser (FEL).Then DESY director-general Albrecht Wagner on Hamburg: every local resident has heard of party guests were granted "ein Sneakpreview" proudly welcomed many special guests. DESY and is proud of the laboratory. of the DESY exhibition, Light for the New Particular welcomes were extended to 88- Strong emphasis was given toTESLA, a plan Millennium, before the public opening. year-old Willibald Jentschke, a founding father fora future TeV linear electron-positron col­ The exhibition hall will eventually become and first director-general of the laboratory lider running 33 km from DESY into Schleswig- an experimental area for the FEL project from 1959 to 1970, and to Mrs Becker-Wiik, Holstein. Ute Erdsiek-Rave, Schleswig- (p26). However, Albrecht Wagner is keen to widow of Bjorn Wiik, who was DESY director- Holstein Minister for Education, Science, find a permanent home for the exhibition, general from 1993 until his tragic death last Research and Culture, joked that "Hamburg perhaps as a cornerstone of a new science year. Wagner paid tribute to Wiik as a "great for once needs Schleswig-Holstein ! " museum in Hamburg. With the laboratory visionary" and revealed that donations to a Minister Bulmahn explained thatTESLA poised at another crossroads in its illustrious research foundation created in his memory would be undergoing detailed scrutiny in career, he looked forward to "another exciting exceeded DEM 75 000 (see box). Germany this year, in comparison with parallel chapter in the DESY history book". Congratulations from German Chancellor projects in the US and Japan. It is, she Alison Wright, CERN.

I James Stirling is Institute will set out to make additonal contri­ UK phenomenology director-designate butions to both the experimental and the of the new UK wider UK theoretical programmes. Research centre is created Institute for Particle will encompass accelerator and non-accelera­ Physics tor measurements, and the emphasis of the After several months of negotiations, the UK i j4 |L Phenomenology at research should evolve with the UK experi­ Particle Physics and Astronomy Research • ^^^h^tÊ^^ 1 Durham. mental particle physics programme. Council has announced the establishment of a key area. Phenomenology (the analysis, Experimentalists will participate in the activi­ an Institute for Particle Physics comparison and interpretation of data) is the ties of the new institute, which will host an Phenomenology at Durham University.The bridge between theory and experiment. extensive visitor programme and hold work­ director-designate is James Stirling. Durham already has a considerable inter­ shops and summer schools for the benefit of The aim is to establish a broad-based, national reputation in this field (see "http:// the whole UK particle physics community.The internationally competitive research activity in durpdg.dur.ac.uk/HEPDATA").The new institute is expected to start up in October.

6 CERN Courier July/August 2000 NEWS

Meeting the ALICE data challenge Imagine trying to record a symphony in each.The first, HPSS, is the fruit of a a second.That is effectively what CERN's collaboration between industry and ALICE collaboration will have to do when several US laboratories.The second, the laboratory's forthcoming Large CASTOR, has been developed at CERN. Hadron Collider (LHC) starts up in Although each component of the 2005. Furthermore, that rate will have to system had been tested individually be sustained for a full month each year. and shown to work with high data rates, ALICE is the LHC's dedicated heavy- this year's tests have demonstrated the ion experiment. Although heavy-ion old adage that the whole is frequently running will occupy just one month per greater than the sum of its parts: prob­ year, the huge number of particles pro­ lems only arose when all of the duced in ion collisions means that ALICE component systems were integrated. will record as much data in that month The tests initially achieved a data rate as the ATLAS and CMS experiments plan of 60 Mbyte/s with the whole chain to do during the whole of the LHC running smoothly. However, then prob­ annual run.The target is to store one lems started to appear in the Linux petabyte (1015 bytes) per year, recorded Alice in gigabyteland. This simulation shows a fraction of operating system used in the DAQ at the rate of more than 1 Gbyte/s.This the tracks in a lead-ion collision, as would be seen by the system's PC farms. Because Linux is not is the ALICE data challenge, and it ALICE detector at CERN's LHC collider. a commercial product, the standard dwarfs existing data acquisition (DAQ) way of getting bugs fixed is to post a applications. At CERN's current flagship message on the Linux newsgroups. accelerator LER for example, data rates However, no-one has previously pushed are counted in fractions of 1 Mbyte/s. Linux so hard, so solutions were not Even NASA's Earth Observing System, readily forthcoming and the team had which will monitor the Earth day and to work with the Linux community to night, will take years to produce a find their own. petabyte of data. That done, the rate was cranked up Meeting the challenge is a long-term and failures started to occur in one of project, and work has already begun. the CERN network's many data People from the ALICE collaboration switches.These were soon overcome - have been working with members of thanks this time to an upgrade provided CERN's Information Technology Division by the company that built the switches - to develop the experiment's data acqui­ and the rate was taken up again. Finally sition and recording systems. Matters the storage systems had trouble are further complicated by the fact that One of CERN's StorageTek tape silos used in the ALICE absorbing all of the data. When these the ALICE experiment will be situated data challenge. problems were ironed out, the target several kilometres away from CERN's peak rate of 100 Mbyte/s was achieved computer centre, where the data will be was to run the full system at a data transfer for short periods. recorded.This adds complexity and makes it rate of 100 Mbyte/s - 10% of the final num­ At the end of April the ALICE data challenge even more important to start work now. ber. This was scheduled for March and April team had to put their tests on hold, leaving Standard components - such as CERN's 2000 so as not to interfere with CERN's exper­ the CERN network and StorageTek robots at network backbone and farms of PCs running imental programme, which will get up to the disposal of ongoing experiments and test the Linux operating system - will be used to speed in the summer. beams. During the tests, more than 20 Tbyte minimize capital outlay.They will, however, be Data sources for the test were simulated of data - equivalent to some 2000 standard reconfigured for the task in order to extract the ALICE events from a variety of locations at PC hard disks - had been stored.The next maximum performance from the system. Data CERN. After being handled by the ALICE DAQ milestone, scheduled for 2001, is to run the will be recorded by StorageTek tape robots system (DATE) they were formatted by the system at 100 Mbyte/s in a sustained way installed as part of the laboratory's tape- ROOT software, developed by the global high- before increasing the rate, step by step, automation project to pave the way for energy physics community.The data were then towards the final goal of 1 Gbyte/s by 2005. handling the large number of tapes that will sent through the CERN network to the com­ The ALICE data challenge team may not yet be required by LHC experiments. puter centre, where two mass storage systems have made a symphony, but the overture is The first goal for the ALICE data challenge were put through their paces for two weeks already complete.

CERN Courier July/August 2000 7 NEWS

Higgs is honoured in Edinburgh

As part of the recent UK Institute of Physics conference, Particle Physics 2000, in Edinburgh, a special symposium was held to celebrate the 70th year of Peter Higgs, after whom the elusive "Higgs field" is named.This field and its particles are responsible for the spontaneous symmetry breaking of the sym­ metry of electroweak interactions, so that, for example, the W and Z carriers of the weak force are heavy particles, while the electro­ Peter Higgs - 70th birthday. At a recent magnetic photon remains massless. Finding symposium in Edinburgh to mark the event, the Higgs particle(s) is today's major particle he was presented with a T-shirt with a picture physics goal. of his grandson - "the lightest Higgs". The event opened with a talk by current Nobel prizewinner Gerard't Hooft on the early rent experimental search for the Higgs at LER he wanted to move the administration build­ days of gauge theories, in which he reminded The afternoon concluded with a lively talk ing to the pit! the audience that in the 1960s these theories by former CERN director-general Chris A theme of the meeting was that the Higgs is were widely regarded as of little relevance to Llewellyn Smith on his long association with everywhere. In a public lecture by Frank Close particle physics. However, his supervisor, the search for the Higgs boson, which began on the origins of asymmetry, Higgs was seen to Martinus Veltman, insisted that all of his stu­ as the theory convenor of a workshop in break the symmetry of an empty Coke can on dents read an obscure paper from the 1950s 1980. He gave a vivid description of the which Close was balancing, causing Close's by Yang and Mills, so helping the 1970s resur­ physics involved in engineering the LHC col­ potential to collapse into an asymmetric state. gence of gauge field theories. lider, including a picture of the CERN At the banquet, Ken Peach, director of In the following talks, Peter Zerwas (DESY) administration building apparently "relocated" particle physics at Rutherford Appleton reviewed the phenomenology of the Higgs to one of the LHC experimental caverns. He Laboratory, gave a lecture from the pulpit of particle at current and future colliders, and had used this to show the CERN Council how the former Highland Kirk. In this suitably PedroTexeira-Dias (CERN) described the cur- big the pits needed to be, and was asked why Calvinist setting, he recalled his misspent > CMS contractors receive LHC collaboration awards Three contractors involved in CERN's forth­ ence to the terms and deadlines of a contract, coming CMS experiment's magnet project a good working relationship and exceptional became the first beneficiaries of the collab­ performance in terms of innovation. oration's new awards scheme on 5 June. In The first three awards were made during a the two-tiered scheme, major contractors CMS collaboration meeting at CERN. It is no deemed by the collaboration to have delivered accident that they all went to contractors exceptional service will receive the CMS working on the experiment's magnet, since Crystal Award. Other contractors are eligible that is the furthest advanced component of for the CMS Gold Award. the new experiment. A Crystal Award went to CMS has initiated the scheme as a moti­ Germany's Deggendorfer Werft und Eisenbau vating factor for all of its contractors, and as a (DWE) GmbH, principal contractor for the way of rewarding excellence. A panel of five CMS magnet yoke. DWE delivered the fifth and has been established to consider award final wheel for the barrel part of the yoke on Industrial excellence for physics - the nominations made by CMS project leaders, time and within budget just before the meet­ Crystal Award presented to Deggendorfer and to make recommendations to the experi­ ing began. Gold Awards were presented to two Werft und Eisenbau (DWE) GmbH by the ment's Collaboration Board. Criteria of DWE's subcontractors: Izhora of St CMS collaboration at CERN's LHC collider. considered by the panel include strict adher­ Petersburg, which produced the 120 forged t>

8 CERN Courier July/August 200C NEWS

youth as a student in Edinburgh, but seemed to remember attending a few field theory lectures by Higgs, which may account for his CERN and Pakistan subsequent career. More recently he recalled an L3 speaker giving a seminar in Edinburgh describing the failure to find a Higgs at LER at the end of which it was pointed out that there strengthen agreement was in fact a Higgs in the audience. However, the most moving part of the Fest Signed in Islamabad in May was an adden­ Centre for Physics at Quaid-i-Azam University, belonged to Higgs, who sported a T-shirt of his dum to the Memorandum of Understanding Islamabad, will also supply 432 resistive plate grandson, indicating the existence of a sec­ between CERN and Pakistan, covering chambers (RPCs) for the CMS forward muon ond light Higgs (evidence for super- increased Pakistani involvement in the CMS system as part of a collaboration that also symmetry?). He received an honorary fellow­ experiment for CERN's LHC collider. involves China, Italy, Korea and the US. In addi­ ship of the Institute of Physics, and a piece of Pakistan is supplying six giant 25 ton support tion the front-end electronics boards for RPC an LHC magnet from his colleagues, to which feet for the main "barrel" magnet of the CMS read-out will be manufactured in Pakistan. he responded in typically modest fashion. detector, as well as material for the magnet A major CERN delegation was recently in Apparently the famous Higgs particle was the itself. Under the new agreement the National Pakistan for the signing of the new agreement. result of only three weeks' work in the mid- On the right foot: CERN 1960s.The first two weeks were spent writing director-general Luciano a paper and having it rejected by the referee Maiani at Taxila, Pakistan, on the grounds that quantum field theory was with one of the 25 ton obscure and of little interest.The referee sug­ support feet for the gested that the paper might be improved by magnet of the CMS the addition of some practical consequences experiment at CERN's LHC .of the theory.The third week was spent provid­ collider. These ing these examples, which included the Higgs components are supplied particle.The audience, which included a large by Scientific Engineering fraction of graduate students, was suitably Systems of Taxila as part awestruck by the idea that a mere three of Pakistan 's contribution weeks' work might be sufficient to get a parti­ to the CMS collaboration. cle named after you. Steve Playfer, Edinburgh.

Islamabad, Pakistan: CERN research director Roger Cashmore (left) and Pakistan Atomic DWE's subcontractors, Izhora and IDAS of Energy Commission (PAEC) member (technical) Samar Mubarakmand sign an addendum the Czech Republic received Gold Awards. to the Memorandum of Understanding between CERN and Pakistan covering increased Pakistani involvement in the CMS experiment for CERN's LHC collider. Behind them are (left iron blocks making up the magnet yoke, and to right) CERN advisor on non-member state matters John Ellis, Hafeez Hoorani of the ZDAS of the Czech Republic, which made the National Centre for Physics, PAEC chairman Ishfaq Ahmad, National Centre for Physics brackets that will hold them all together in 12- director Riazuddin, CERN director-general Luciano Maiani, Quaid-i-Azam University vice- sided wheels. chancellor Tariq Siddiqui and CMS collaboration resources manager Diether Blechschmidt.

CERN Courier July/August 2000 9 NEWS

Czech physics scene is growing

At the ECFA meeting in Prague. Left to right: ECFA chairman Lorenzo Left to right: Jiri Niederle, president of the CERN/Czech Foa, Czech student Peter Homola and Czech ECFA representative collaboration committee; CERN director-general Luciano Maiani; Vladislav Simak. and Czech Deputy Foreign Minister Hynek Kmonicek.

Particle physics in the Czech Republic is teaching".This has now changed.There has stantial increase in the number of high-energy maturing fast.This was the message that also been a drastic reduction in the number of physicists in the Czech Republic since the emerged from the European Committee for people employed by the academy, from about ECFA last visited the country in 1994.The Future Accelerators (ECFA) during its continual 13 000 to about 6500. Several institutes of number of theorists has increased from 37 to tour of CERN member states as it recently the academy have been closed. 51 and that of experimentalists from 39 to surveyed national activities at a meeting at After several difficult years there is now 94.This is partially due to the change of orien­ the Masaryk Hostel of the Czech Technical optimism in the air.The state support of R&D - tation of scientists already in the system.The University, Prague. (The hostel is named after 0.4% of national GNP in 1999 - is expected to average age of permanently appointed staff is Tornas Masaryk, who was the first president of be 0.6% in 2000 and to increase to 0.7% by high - 48 for theorists and 51 for experimen­ the Czechoslovakian Republic, from 1918 to 2002. One difficult remaining problem con­ talists. 1935.) cerns how to attract young people, who are So far the Delphi experiment at LEP has At the ECFA meeting, policy issues in the badly needed, because the average age in this been the central activity of Czech experimen­ Czech Republic were presented by M Potucek sector is high.The salaries offered to young tal physics. For the future, ATLAS at the LHC and Pavel Chraska, respectively deputy chair­ people are simply not attractive enough. will take over this role. However, Czech physi­ man and a member of the national Research The status of high-energy physics in the cists also take part in a range of other and Development Council.This agency is Czech Republic was reviewed by J Niederle, experiments at CERN (ALICE, CERES, DIRAC, proposing new rules for the organization president of the National Committee for ISOLDE, NA57) as well as in several R&D finance of research and development.The Collaboration with CERN, and by J Hosek.The projects. Outside CERN, Czech physicists keyword in these presentations was "changes", good news here is that there has been a sub- participate in the DO experiment at Fermilab of which there have already and in HI at DESY. Since 1998 been many since the 1989 Charles University, Prague the Czechs have also been "velvet revolution", but there involved- with the Auger cosmic- are more to come. The oldest university in central Europe, Charles University in Prague, was ray project. One major purpose is to founded in 1348 by Charles IV, then Holy Roman Emperor and King of Across this now wide spec­ make the Czech system Bohemia. Austrian physicist and philosopher Ernst Mach was a professor trum - in R&D, detector more compatible with that of there for 28 years ( 1867-95), during which time he proposed Mach's building, data analysis and the European Union coun­ principle, which greatly influenced Albert Einstein's thinking in the theory - Czech physicists make tries. For example, scientific formulation of his theory of gravity. Mach also served as rector of the an important contribution to research was traditionally University. Appointed professor at the university in 1911, Albert Einstein the world particle physics effort carried out almost entirely at became aware there of the importance of tensor calculus for his work on in general and to the CERN the institutes of the Academy general relativity. His student at Prague was Otto Stern. When Einstein left programme in particular. At the of Sciences while the univer­ Prague the following year, he was succeeded by Philipp Frank. meeting, Czech physicists sities were "just for described this contribution.

10 CERN Courier July/August 2000 NEWS

Antiprotons spring surprises

Experiments at CERN's low- proton. Surprisingly, at low energy antiproton ring (LEAR), antiproton momentum, the closed in 1996, brought many antiproton-deuteron and very-high-precision and some­ antiproton-helium annihi­ times surprising antiproton lation cross-sections drop to results. Some continue to the proton-antiproton level or appear, the latest being the even below it. apparent independence of the An accurate analysis of size of the target of the these annihilations shows antiproton-nucleus annihi­ that this is nota kinematic lation rate at very low energy. effect; it is a direct result of Clearly antiproton annihilation the dynamics ofthe antipro­ is a mysterious business. JO ton-nucleus interaction. Antiproton-nucleus annihi­ This was confirmed inde­ lation was measured at LEAR pendently by another LEAR by the OBELIX experiment at experiment - PS207 - which very low antiproton momenta, measured, for the first time, downto40MeV/c.This the shift and the broadening momentum seems quite large ofthe antiproton-deuteron with respect to the character­ atomic ground state.This istic momentum in extremely difficult experiment particle-antiparticle systems showed that the width of this bound by electromagnetic level, entirely determined by attraction (Coulomb force). the annihilation process, is For proton-antiproton, this is approximately the same for ofthe order of 4MeV/c. Mysterious annihilation. Proton-antiproton (red triangles), antiproton- antiproton-proton and Nevertheless, this attraction deuteron (green bullets) and antiproton-deuteron (blue squares) antiproton-deuteron atoms. appears to be important and annihilation as measured by the OBELIX experiment at CERN's LEAR low- A geometrical picture of can even affect the annihi­ energy antiproton ring. The values are weighted by the square of the annihilation would suggest lation rate. relative velocity ofthe annihilating particles. The curves show the results of that the probability of this In fact, in this energy range, a phenomenological analysis ofthe data. However, the large disparity process should increase with Bethe's usual 1/v law is between the curves - the deuteron and helium cases higher than the number of possible anni­ replaced by a 1/v2 one, where proton-antiproton at higher momenta and lower at lower momenta - is not hilating partners - the number v is the relative velocity ofthe totally understood in terms ofthe basic nucléon-antinucleon annihilation. of nucléons in nuclei. interacting particles. However, these experiments This 1/v2 regime was predicted in 1948 by These cross-sections are multiplied by the demonstrate clearly that this is not the case. Wignerand is well known in atomic physics. In square ofthe relative velocity. For the proton- To understand the mystery, these experi­ nuclear physics, in contrast, one usually antiproton system, the situation is very clear: ments should be continued at lower energies encounters electromagnetic repulsion one can see that the product tends to a con­ and with heavier nuclei, not only to understand between protons, which gives rise to an expo­ stant value with decreasing antiproton the dynamics ofthe annihilation process but nential decrease ofthe reaction rate at low momentum. For a 1/v behaviour, this product also to measure the cross-sections. energies, a phenomenon that is particularly should tend to zero. For the deuteron and This knowledge would be important, in important in nuclear astrophysics. helium cases, the analysis is more compli­ particular for astrophysicists, who search for The OBELIX experiment, for the first time, cated. antimatter in the universe and need to know investigated with very high precision the This change of regime is instructive but not about the properties of low-energy behaviour of the reaction rate in a system with really unexpected.The most interesting obser­ matter-antimatter interaction. CERN's anti- Coulomb attraction. In the figure, the meas­ vation comes from the comparison ofthe proton decelerator (AD), currently starting ured antiproton-proton, antiproton-deuteron values of these three cross-sections. At high operations, will be a powerful tool in obtaining and antiproton-helium annihilation cross- energies they are quite different - the antipro­ this precious antimatter information. sections are presented as a function of ton-nucleus annihilation cross-sections are Konstantin Protasov, Institut des Sciences antiproton momentum. several times that for antiproton- Nucléaires, Grenoble.

CERN Courier July/August 2000 11 NEWS

Celebrating the centenary of a conscience

One ofPauli's last major public appearances At the Zurich lectures celebrating the Ludwig Faddeev (left) of St Petersburg, who was at the 8th International ("Rochester") centenary of Wolfgang Pauli's birth. Left to spoke on "Non-Abelian gauge theories", with Conference on High Energy Physics, hosted right: Riccardo Barbieri (Pisa), who spoke on Valentine Telegdi, who began his by CERN in the summer of 1958. "From the neutrino hypothesis to the experimental physics career at ETH. Standard Model"; André Rubbia (ETH Wolfgang Pauli, the "conscience of physics" Zurich), who covered "Neutrino experiments: do in this respect." was born in Vienna on 25 April 1900. Among past, present and future"; and Christoph The first three talks in the session were by the events organized to celebrate the Pauli Schmid (ETH Zurich). Hideki Yukawa, Werner Heisenberg and Pauli. centenary was a series of public lectures, Immediately after Heisenberg's talk, "Non­ Wolfgang Pauli and Modern Physics, at the ETH fundamental ideas. So what you shall hear are linear spinor theory with indefinite metric", (Swiss Federal Technical High School) Zurich, substitutes for fundamental ideas, and it Pauli said sternly: "Regarding the papers of where Pauli spent his career from 1928 until works in the same way as I am the substitute Heisenberg and collaborators on the spinor his death in 1958, except for an interval during for a rapporteur. So you will also see that model...I reached the conclusion that they are the Second World War.The Zurich lectures there are two kinds of ignorance - rigorous mathematically objectionable." focused on Pauli's life and work, and his scien­ ignorance and more clumsy ignorance.You Heisenberg persisted, but Pauli eventually tific legacy, with a distinguished list of will also hear that many speakers will want to retorted again: "I completely disagree with the speakers. A Pauli exhibition, currently in Zurich, form new credits for the future. I am person­ answer of Heisenberg - not only unnatural will be moved to CERN later this year.* ally not very willing to give such credits but it but mathematically impossible." Pauli discovered many of the 20th century's is for everybody to choose what he wants to Heisenberg countered: "Of course I again major new directions for modern physics and disagree completely with what Pauli said..." went on to lay the foundations for much of Pauli polemics After the young Murray Gell-Mann (aged 28) what was to come - quantum mechanics, the tried to establish some calm and order Exclusion Principle, electron spin, quantum Pauli became legendary not only for his between the warring quantum veterans, field theory, the neutrino hypothesis, spin and physics but also for his vituperation and Heisenberg commented: "I agree completely statistics, among others. invective. Some examples: with what Gell-Mann just said. But at the same Contemporary physics is, of course, his At a seminar given by a young researcher: time I propose to postpone the discussion for greatest monument, but another is his prolific "Your first equation is already wrong, and half a year and then we will know more." correspondence with contemporary scientists. your second does not follow from it"; The ever-implacable Pauli concluded: "I think CERN has become the home of this carefully Of a young physicist, Pauli retorted: that is superfluous. In half a year the answer accumulated and maintained Pauli archive, "What, so young and already unknown?" will be the same as Gell-Mann gave just now." the source for a four-volume series of scien­ The Vienna-born Pauli asked another Half a year later, Pauli was dead, but his tific correspondence, published by Springer. physicist: "When did you leave Vienna?" name will live for ever. One of Pauli's last major public appear­ "1938," he repied. "I left in 1918," retorted *The Pauli exhibition will be in CERN's Main ances was at the 8th International Pauli. "My intuition was always good." Building from 17 August until 26 September, ("Rochester") Conference on High Energy The festschift Das Gewissen der Physik and a ceremony will take place in the Council Physics, hosted by CERN in Geneva on 30 (the Conscience of Physics), edited by Chamber on Monday 11 September, begin­ June - 5 July 1958. This was the first time that Charles Enz and Karl von Meyenn, from a ning at 4.30 pm.This will include short this meeting had been held outside the US. As 1983 meeting in Vienna to mark the 25th presentations from Maurice Jacob (chairman chairman of the Fundamental Ideas session, anniversary of Pauli's death, contains of the Pauli Committee), Konrad Osterwalder Pauli began: among a wealth of contributions a (Rektor of the ETH Zurich), Luciano Maiani "This session is called 'fundamental ideas' memorable collection of such anecdotes, (director-general of CERN) and Charles Enz in field theory, but you will soon find out, or compiled by ValTelegdi. (University of Geneva) on Pauli's life and have already found out, that there are no new legacy.

12 CERN Courier July/August 2000