VOLUME 39 NUMBER 8 OCTOBER 1999

200 GeV - a major leap for LEP

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) 1999 Diversified Technologies, Inc. PowerMod™ is a trademark of Diversified Technologies, Inc. CONTENTS

Covering current developments in high- energy physics and related fields worldwide

CERN Courier is distributed to Member State governments, institutes and laboratories affiliated with CERN, and to their personnel. It is published monthly except January and August, in English and French editions. The views expressed are not necessarily those of the CERN management. CERN Editor: Gordon Fraser CERN, 1211 Geneva 23, Switzerland E-mail [email protected] Fax +41 (22) 782 1906 Web http://www.cerncourier.com News editor: James Gillies COURIER VOLUME 39 NUMBER 8 OCTOBER 1999 Advisory Board: R Landua (Chairman), F Close, E Lillest0l, H Hoffmannt C Johnson, K Potter, P Sphicas

Laboratory correspondents: Argonne National Laboratory (USA): D Ayres Brookhaven, National Laboratory (USA): P Yamin Cornell University (USA): D G Cassel DESY Laboratory (Germany): Ilka Flegel, P Waloschek Fermi National Accelerator Laboratory (USA): Judy Jackson GSI Darmstadt (Germany): G Siegert INFN(ltaly):APascolini IHEP, Beijing (China): Qi Nading Jefferson Laboratory (USA): S Corneliussen JINR Dubna (Russia): B Starchenko KEK National Laboratory (Japan): A Maki Lawrence Berkeley Laboratory (USA): B Feinberg Los Alamos National Laboratory (USA): C Hoffmann Nucleus of quasar 3C380 p!3 Neutrino interactions p!9 LEP experiments go cosmic p32 NIKHEF Laboratory (Netherlands): Margriet van der Heijden Novosibirsk Institute (Russia): S Eidelman Orsay Laboratory (France): Anne-Marie Lutz News PSI Laboratory (Switzerland): P-R Kettle Rutherford Appleton Laboratory (UK): Jacky Hutchinson First K2K events seen at KEK lab. MINOS to explore neutrino mass. Saclay Laboratory (France): Elisabeth Locci Lepton-photon symposium at Stanford. First beams of nuclei circulate IHEP, Serpukhov (Russia): Yu Ryabov Stanford Linear Accelerator Center (USA): M Riordan rings at Brookhaven's RHIC. WASA meson detector inaugurated. ISAC TRIUMF Laboratory (Canada): M K Craddock achieves IOJUA. Produced for CERN by Institute of Physics Publishing Ltd I0P Publishing Ltd, Dirac House, Temple Back, Physicswatch 10 Bristol BS1 6BE, UK Tel. +44 (0)117 929 7481 13 E-mail [email protected] Astrowatch Web http://www.iop.org

Publishing director: Mark Ware Features Publisher: Mark Wormald 200 GeV achieved for 2000 14 Art director: Andrew Giaquinto Production editor: Teresa Ryan Not a leap year, but an LEP decade Technical illustrator: Alison Tovey Sales manager: Harvey Stockbridge Advertising manager: Jo Nicholas Neutrino physics gains weight 19 Classified sales: Chris Thomas Where there are neutrinos there's always controversy Advertisement production: Katie Graham Product manager: So-Mui Cheung A good BaBargain 21 Advertising: Jo Nicholas or Chris Thomas Tel. +44 (0)117 930 1026 New experiments jostle to look at the physics of B particles E-mail [email protected] Fax +44 (0)117 930 1178 Why does CP vioiation matter to the universe? 24 General distribution: Jacques Dallemagne, CERN, 1211 Geneva John Ellis looks at a key to the behaviour of elementary particles and 23, Switzerland. E-mail [email protected] In certain countries, to request copies or to make address changes, the Big Bang contact: China: Chen Huaiwei, Institute of High Energy Physics, P.O. Box 918, Beijing, People's Republic of China Looking at cosmic rays with accelerator detectors 29 Germany: Gabriela Heessel or Astrid Nagel, DESY, Notkestr. 85, Making the most of big instrumentation 22603 Hamburg 52 Italy: Mrs Pieri or Mrs Montanari, INFN, Casella Postale 56, 00044 Frascati, Roma Bookshelf/New products 34 United Kingdom: Su Lockley, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire 0X11OQX USA/Canada: Janice Voss, Creative Mailing Services, P.O. Box 1147, People 35 St Charles, Illinois 60174. Tel. 630-377-1589. Fax 630-377-1569

Published by: European Laboratory for Particle Physics, CERN, 38 1211 Geneva 23, Switzerland. Tel. +41 (22) 767 6111 Recruitment Telefax +41 (22) 767 65 55

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© 1999 CERN

ISSN 0304-288X

Cover: In 10years, CERN's 27 km LEP electron-positron ring has progressed from 45 to 100 GeV per beam, testifying to the foresight of the design team (pl4).

CERN Courier October 1999 3 Leading supplier of electronics to physics experiments for over 30 years:

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Tel: +41-22-719-2228 • Fax: +41-22-719-2230 • e-mail: [email protected] • www.lecroy.com Offices in France, Germany, Italy and United Kingdom NEWS First K2K events seen at KEK lab

During 22 days of stable data-taking in June, The first K2K event seen by Supfcr-Kamiokaitde the K2K Long Baseline Neutrino Oscillation Rttft 7436 Event 14054126 Super-Kamiokande. The colour of experiment, connecting the Japanese KEK the dots indicates the arrival time Laboratory with the detectors in the Kamioka of the light detected by each mine 250 km away, observed four neutrino photomultiplier and the size interactions in the inner Super-Kamiokande shows the amount of charge. The detector.This is the first step towards the diamond shows the entrance verification of the neutrino oscillation results point of the neutrino and the given by the Super-Kamiokande last year. crosses give the coordinates of One event occurred inside the 22.5 kiloton the interaction point The "fiducial volume" (2 m from the inner photo- direction of the incoming multiplier tubes) and another three events neutrino given by these two occurred outside.The event characteristics are positions is consistent with it FIRST K2K EVENT consistent with a neutrino interaction in water. coming from the Japanese KEK in SUPER-K More importantly, all four events happened Laboratory, 250 km away. within 1 |JS of the time expected for neutrinos 1000 1500 200 generated at KEK. Times (ns) No further events were seen in the inner detector within 50 LIS of the expected time. Before reaching the distant Super- Kamiokande detector, the neutrinos pass through a "near detector" on the KEK site. Both detectors have a clock synchronized by the Global Positioning System (GPS), which is accurate to 100 ns.The probability that each of the four events comes from an atmospheric neutrino interaction is estimated to be a few parts in 10 000. The K2K experiment began tuning the beamline, beam monitors, magnetic horn system and the near detector on 5 March. All of the detector components worked as expected. During an engineering run from March to May, physicists ensured that neutrinos were being sent in the direction of Super-Kamiokande to an accuracy of An aerial view of the K2K neutrino beamline at the Japanese KEK Laboratory. At the bottom 0.3 mrad and that the flux and the profile of left are the KEK 12 GeV Proton Synchrotron and its north counter hall. The extracted proton the beam were as expected. beam is bent around towards the near detector (small white building, top right) and exits During the summer shutdown period, the towards Kamioka, 250 km away. KEK beamline group will be improving the Shown here is the near transmission of the primary proton beamline detector of the K2K and will increase the current of the magnetic experiment. The silver horns.The KEK accelerator succeeded in tank in the back is a circulating 6.5 x 1012 protons in nine bunches 1 kiloton water in the main ring in June and will look for a Cherenkov detector and further improvement in intensity.Thus, K2K at the front is the muon hopes to have more neutrinos in the coming detector, consisting of run, which will be starting in late October. \ -3 iron plates and The K2K experiment is an international scintillation fibre collaboration of institutes from Japan, Korea \... ^ planes. and the US...... ;^J I1:

CERN Courier October 1999 5 NEWS

MINOS to explore neutrino mass

evidence of neutrino mass and would allow physicists to begin to calculate just how much mass the particles possess. Locating the detector far below ground screens out cosmic rays that would otherwise flood the detector with irrelevant signals. Earlier neutrino experiments detected fewer naturally-occurring neutrinos than expected, so they concluded that one type of neutrino had oscillated into another and, hence, had "disappeared" from detection. In contrast, the MINOS experiment could detect not only the Left to right: Earl Peterson, University of Minnesota; John O'Fallon, US Department of disappearance of muon neutrinos, but event­ Energy; Michael Witherell, Fermilab director; Stan Wojcicki, Stanford University and MINOS ually their appearance as neutrinos of a spokesperson; Paul Maurer, Minnesota Department of Natural Resources (which owns the different type - tau neutrinos (pl9). mine); Christine Maziarand Ed Wink, University of Minnesota. To monitor the evolution of the neutrino beam, MINOS will use two detectors - the Deep in a former Minnesota iron mine, quences for our understanding of the nature "near detector" at Fermilab and the scientists and government officials recently and distribution of mass in the universe. 5400 tonne "far detector" in the Soudan wielded pickaxes to chip away, at least sym­ For the MINOS experiment, 120 GeV tunnel.The design initially proposed foresees bolically, at the mysteries surrounding the protons from Fermilab's newly commissioned fine-grained iron-scintillator sandwich subatomic particles known as neutrinos. Main Injector accelerator will be used to gen­ calorimeters providing both tracking and The miners-for-a-day in the Soudan mine erate an intense beam of muon neutrinos energy deposition information. took the first steps in carving out a huge directed towards the underground Soudan On the other side of the Pacific Ocean is a cavern, half a mile underground, that will detector, 730 km away. Neutrinos are reluctant similar study - K2K - using neutrinos provided become home to a 5000 ton particle to interact with matter and can pass through by the accelerator at the Japanese KEK detector. Physicists of the 200-member Main the Earth without any effect. However, inter­ Laboratory inTsukuba (p5).The particles are Injector Neutrino Oscillation Search (MINOS) action is probability not zero, so an intense directed towards the Super-Kamiokande experiment will use the detector to explore the beam and/or a large detector will record underground detector 250 km away. K2K is question of neutrino mass. some interactions. recording its first data. Physicists once believed that neutrinos were From early 2003, MINOS collaborators will At CERN, physicists are studying a proposal massless, zipping through matter at the speed use the detector to determine whether some to direct a neutrino beam towards the Italian of light. However, recent results (CERN Courier of the muon neutrinos in the beam have Gran Sasso underground laboratory. Curiously, September 1998 pi) suggested that these changed to another type, known as tau like MINOS, it is 730 km from the accelerator elusive particles have a small mass. Even a neutrinos. Such a change, or oscillation from neutrino source (CERN Courier November tiny neutrino mass would have major conse- one type to another, would constitute clear 1998 pl3). Lepton-photon symposium at Stanford

The major international focus of high-energy Both of these interlocking biennial physics in odd-numbered years is the meetings are sponsored by the International International Symposium on Lepton-Photon Union of Pure and Applied Physics (IUPAP) Interactions at High Energies, which took and the venues follow a traditional pattern, place this year on 9-14 August at Stanford rotating between Europe (Western and University, California. Several reports from the Eastern), North America and Asia. meeting feature in this issue. Next year the ICHEP will be held in Osaka, The lepton-photon symposia alternate with Japan, from 27 July to 2 August.The 2001 the International Conference on High-Energy Lepton-Photon Interaction Symposium will Stanford University, the venue for this year's Physics (ICHEP), often known as the take place in Rome and the 2002 ICHEP in International Symposium on Lepton-Photon "Rochester" series, after the founding venue. Amsterdam. Interactions at High Energies.

6 CERN Courier October 1999 NEWS

First beams of nuclei circulate rings at Brookhaven's RHIC

During August, work continued to establish circulating beams of nuclei in the two rings of Brookhaven's Relativistic Heavy Ion Collider (RHIC). Equipped with superconducting magnets, the machine operates at 4.6 K. The beam was injected and stored in the first ("blue") ring. Lifetimes of up to 45 min and modest acceleration - about 1 GeV per nucleon - were achieved. A few apparent obstacles will be investigated when the ring is warmed up. Thousands of turns of beams have been seen briefly in the second ("yellow") ring, with successful radiofrequency capture. Long lifetimes have not yet been established, nor has acceleration been performed. While no apparent obstacles have been found in this ring, steering and second turn closure in the injection region were found to be more difficult than in the first ring, as was steering through the dump area. Beams are next expected in RHIC in Work on the cryogenic system for Brookhaven's Relativistic Heavy Ion Collider. Equipped December. with superconducting magnets, the machine operates at 4.6 K. (R Stouten burgh.)

Earlier this year a meeting took place between members of the directorates of Brookhaven National Laboratory and the Joint Institutes for Nuclear Research (JINR), Dubna, near Moscow. The timing of the meeting was chosen to allow visitors from JINR to tour the RHIC complex prior to the start of RHIC operations. The purpose was to discuss areas of mutual interest for scientific collaboration. Brookhaven director John Marburger (right) and JINR director Vladimir Kadyshevsky signed a protocol of understanding, regarding activities that will be accomplished in 1999 in areas of mutual interest. A key element of the agreement is to establish a PC farm at JINR to support JINR's ability to participate fully in the analysis of data and the production of scientific results from RHIC, Fermilab and CERN. The establishment of the farm has already been achieved since the meeting.

CERN Courier October 1999 7 NEWS

WASA meson detector inaugurated

The two halves of the WASA caesium iodide calorimeter barrel. A schematic of the CELSIUS storage ring.

During the recent PANIC99 particle/nuclear were brought from CERN to Uppsala in 1983. development of airborne magnets for physics conference (CERN Courier September CELSIUS experiments began in 1990.There Japanese space experiments. Copper of 3 mm p9), CELSIUS/WASA, a new detector facility are two target stations. One is occupied by thickness, corresponding to only 0.18 radi­ for the CELSIUS cooler storage ring, was inau­ CELSIUS/WASA and makes use of protons ation lengths, is placed inside the caesium gurated.The inauguration talk was given by with energies of up to 1.36 GeV. iodide calorimeter barrel, which has 1012 Erwin Gabathuler and the facility was shown The CELSIUS/WASA collaboration involves individual elements. Inside the solenoid are a to conference participants during tours of the groups from Uppsala, Stockholm, Hamburg, plastic scintillator barrel with 146 elements the Svedberg Laboratory - a Swedish national Tubingen, Julich, Warsaw, Moscow, Dubna, and a mini drift chamber with 1738 individual facility for accelerator-based research. Novosibirsk, Osaka and Tsukuba. Studies will straws. The trigger system has to cope with a The name of the laboratory is associated be made of decays and production of light total event rate of 10 MHz. with Svedberg, the 1926 chemistry Nobel mesons from inelastic proton-hydrogen colli­ Already, several years of production experi­ Laureate, who in 1945 took the initiative to sions. CELSIUS/WASA consists of a forward ments, with only the forward part of WASA, build the Gustaf Werner 185 MeV synchro­ part, primarily for measurements of the have provided interesting new information on cyclotron that was, in the early 1950s, the scattered protons, and a central part for mea­ meson production near the kinematical highest-energy accelerator in Western Europe. suring the mesons and their decay fragments. threshold.These measurements will continue, This accelerator, rebuilt into a sector- The targets are hydrogen pellets injected at and studies of rare eta decays are being initi­ focusing synchrocyclotron, is used for high speed (60 m/s) through a tube that ated. Of main interest are suppressed research and also serves as an injector for connects to the CELSIUS beam tube.They are electromagnetic decays and strong decays. CELSIUS (Cooling with Electrons and Storing produced from a liquid jet broken up into These will be used to measure limits of C and Ions from the Uppsala Synchrocyclotron), droplets by a piezoelectric crystal at the noz­ CP symmetries and their relations to the cor­ which is an accelerator and storage ring zle. The stream of 0.03 mm diameter pellets responding symmetries in the kaon system. intended for internal target experiments. can be collimated so that the desired size and Understanding low-energy phenomena in The magnets for the 82 m circumference frequency are reached at the circulating terms of quarks is one of the great challenges CELSIUS ring - formerly used in the CERN g-2 proton beam. of subatomic physics.The rare decay pro­ experiment (to measure the muon's mag­ One key component is the very thin super­ cesses may also unravel surprises that are not netism) and ICE (beam cooling) experiment- conducting solenoid coil, which is a further easily explainable by the Standard Model.

facility. Current experiments focus on the very carried out since late November 1998 (CERN ISAC achieves lOpA short-lived isotope rubidium-74, for which Courier March p7), when ISAC was first com­ measurements of the half-life (65 ms) and missioned with a 1 |JA proton beam. An initial The new isotope separator and accelerator branching ratios are expected to provide test at 100 MA is planned for December 1999. (ISAC) facility at the Canadian TRIUMF labora­ fundamental tests of the weak interaction. Meanwhile, progress is on schedule with the tory passed a milestone on 28 July when the Nuclear shape measurements are also radiofrequency quadrupole and drift-tube proton current on target was raised to 10 |jA, underway using the low-temperature nuclear linac sections for the acceleration of the ions making it the highest intensity isotope separ­ orientation (LTN0) facility from Oak Ridge. to 1.5 MeV/nucleon for nuclear astrophysics ator on-line (IS0L) radioactive ion beam Experiments at lower intensity have been experiments at the end of 2000.

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.1 L PHYSICSWATCH

Edited by Alison Wright Except where otherwise stated, these news items are taken from the Institute of Physics Publishing's PhysicsWatch service, which is available at "http://PhysicsWeb.org". Quantum modelling of the mind

Some of the best minds in biophysics have 1 s. Some say that it is, while others, including modelled as the collapse of a quantum super­ been divided on the question of how to model Stephen Hawking, say that it isn't. Now, Mark position of electrical excitations propagating the workings of the human brain. Mainstream Tegmark of Princeton has weighed in with new in a microtubule. research has concentrated on developing calculations of coherence times for two Whether the model involves neuron firing of complex neural networks to perform the cognitive models. charged ions or propagating excitations in cognitive processes that we call conscious­ The first model describes the thought microtubulesjegmark calculated that the ness. However, others, including Roger process as "neuron firing", where brain influence of nearby ions, by collision or Penrose at Oxford, have argued that impulses are caused by neurons pumping out coulomb interaction, will destroy the consciousness is in fact a quantum effect and sodium ions and absorbing potassium ions. In coherence of the superposed states on very can only reasonably be simulated by a the quantum picture, a neuron can exist in a short timescales (10"20 s for neurons and quantum computer. superposition of firing and non-firing states. 10"13 s for microtubules) - too short for a The big issue in quantum consciousness is In Penrose's alternative model, conscious­ quantum system. coherence time: how long can a superposition ness resides in microtubules - hollow "There is nothing fundamentally quantum of quantum states in the brain persist? For cylinders of protein that act as "scaffolding" to mechanical about the cognitive process in the the brain to be a true quantum mechanical maintain the shape of brain cells. Using tech­ brain", said Tegmark. For the neural network system, the coherence time must be at least niques from string theory, thoughts can be community "it's business as usual". AIP Only 18 clicks Symptoms of supersymmetry of hyperlink Some particle physicists were excited when this information to their existing knowledge of separation they heard rumours that supersymmetry had neighbouring even-even and even-odd nuclei, been found.The rumours were true. However, the experimenters were able to find Two randomly selected Web pages are on the supersymmetry in question is not the correlations in the energy levels that showed average 18 hyperlinks (or clicks) apart. So duality that boldly predicts that every known that nuclear forces are fermion-boson says a group of US scientists who used a half-integer spin ("fermion") particle should symmetric - a property known in the physics technique based on power law distributions, have an as-yet-unseen integer spin ("boson") world as supersymmetry. borrowed from statistical physics, to investi­ partner and vice versa. This is good news for nuclear physicists, gate the topology of the Internet. The team A Swiss-German team has analysed in who now have an additional tool to help them also predicted that, even if the number of depth the energy level spectrum of gold-196, to understand complex nuclear spectra. pages on the Web grows by 1000%, any two which has an odd number of protons (79) However, particle physicists are still waiting for pages will still be only 20 clicks apart. and an odd number of neutrons (117). Adding their supersymmetric day to come. Quantum non-demolition is demonstrated on a single photon

The first repeated measurement of a single After many years of effort, the Parisian shift - Heisenberg's Uncertainty Principle photon has been reported at Ecole Normale researchers have now mastered the tricky won't let you have it every way). Superieure, Paris. Usually light detection is a QND technique and have made repeated This QND technique could become the destructive process, because photons are measurements of a single photon trapped in a basis of a quantum logic gate. absorbed and converted into electrical niobium cavity. In the experiment, a rubidium signals. However, it doesn't have to be that atom is passed through the cavity and the Correction way - the rules of quantum mechanics do photon causes a phase shift in the atom's The e-mail address printed in the actually allow repeated measurements of a wavefunction.The phase shift is detected by advertisement for VAT Vacuum Products on quantum object without destroying it.This is interferometry. Sending atoms through the pl2 of the July issue of CERN Courier was called quantum non-demolition (QND) and cavity again and again repeats the incorrect.The correct address is has been demonstrated for large photon measurement, because the photon remains "[email protected]". fluxes, but never before for a single photon. undisturbed (although it does suffer a phase

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Scratches on the surface of a semiconductor, made using an AFM, can influence the conduction of electrons in the material. Shown here are grooves of 110 nm width, which form an in-plane-gate transistor in a GaAs/AIGaAs sample. vision Scientists at Hannover and Stuttgart have demonstrated a new nanomachining rne power technique to make tiny electronic components. An atomic force microscope to see more (AFM) was used to etch the surface of a semiconductor and form a micrometre-sized deeply. in-plane-gate (IPG) transistor - a device in which the source, drain and gate of the tran­ sistor all lie in a single plane rather than the usual sandwich structure. Ask for your free trial copy First the group formed the semiconductor EXTREME HEAT of IRIS Explorer today quoting from layers of GaAs and AIGaAs, finishing with SEVERE COLD a hard layer of GaAs on top. In the plane reference number 79901 1. DTYPE CONNECTORS between these semiconductor layers, a Tel +44 (0)1865 511245 ULTRA HIGH VACUUM reservoir of electrons collects.Then, by carefully scratching grooves into the surface of Email [email protected] HIGH DENSITY DESIGNS the GaAs with the AFM, conduction channels www.nag.co.uk/iecc for the electrons are defined. LOW PROFILE The experimenters were also able to moni­ CONFIGURATIONS tor the resistance across the etched lines COAXIAL CONNECTORS during fabrication, thereby allowing the 50 OHM IMPEDENCE characteristics of the electronic device to be THERMO COUPLES tuned very accurately. HIGH VOLTAGE With a few more scratches (as tunnelling barriers across the conduction channel), the IPG transistor was transformed into a single- electron transistor that (as its name suggests) ~X~] Ceramaseal is capable of registering the movement of ^penGL I A Division of CeramTec single electrons. AIP •%0 New Lebanon. New York I Tel: +1-518-794-7800

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DEUTSCHE PHYSIKALISCHE GESELLSGHAFT ASTROWATCH

Edited by Emma Sanders Millennium Cosmology not constant 'delayed' by A simulation of the evolution of the universe theory that matches the observed distribution suggests that it is expanding at an accelerat­ of clustering", said Frenk. "Its amazing. I space mission ing rate. This is more evidence for the couldn't believe it when I first saw it!" existence of Einstein's cosmological constant However, to get a perfect match, they needed - a kind of gravitational pressure in space that to use a non-zero cosmological constant. to Saturn acts against the attraction due to mass. This is not the first time that observations Last year the Virgo consortium carried out have implied the existence of a cosmological the largest computer simulation ever, constant. Supernova studies (CERN Courier Hold the champagne! Millennium modelling the evolution of some 1 billion May p9) have also hinted at this and Frenk celebrations throughout the world will be particles.The consortium groups astronomers says that his results are "beautifully consis­ delayed.The culprit is the Cassini-Huygens from Canada, Germany, the UK and the US tent". The group is trying to test its result by space mission, which flew by the Earth in and it is led by Carlos Frenk at Durham carrying out an additional simulation in August in order to pick up speed for its University in the UK. parallel, this time including both dark matter outward journey to Saturn.The energy gained The Durham group has now used the Virgo and gas. First indications are in agreement, by Cassini was lost by the Earth, thus slowing simulation to explain observations of real but there is a greater margin of error. down its orbital motion. However, astronomers galaxies. It used models of galaxy formation The Virgo supercomputer simulations were shouldn't be criticized as party poopers - together with the distribution of matter pre­ carried out at the Max-Planck centre in celebrations will only have to wait an extra dicted by the simulation. Garching, Germany, and the Edinburgh million millionth of a second. "This is the first time that we have had a computer centre in the UK. Picture of the month FUSE lift-off

A new satellite to explore the ultraviolet uni­ verse - the Far Ultraviolet Spectroscopic Explorer (FUSE) - was launched on 24 June. It will investigate the origin and evolution of the lightest elements - hydrogen and deuterium. Deuterium is a valuable indicator of what happened in the early universe, because its formation depended on the temperature and density at that time. The amount of deuterium has been decreasing ever since because it is recycled by nuclear fission in stars. A measure of the relative abundance of hydrogen and deuterium can reveal valuable information about the conditions just a few seconds after the Big Bang. FUSE will also be used to observe the com­ position of interstellar gas and the chemical This radio map shows the nucleus of the quasar 3C380 (left), with emission from a huge jet evolution of galaxies.The satellite will observe 240 light years across blasting out into space to the right. Quasars are galaxies with the far-ultraviolet spectrum from 90 to supermassive black holes at their centre. Radio emission is caused by synchrotron radiation 120 nm with more than 10 000 times the from electrons moving close to the speed of light along the huge magnetic fields produced sensitivity previously attainable. by the black hole. 3C380 is the first radio source processed with the new European Very FUSE was built by collaborators in France, Long Baseline Interferometry (VLBI) Network Processor which was commissioned this Canada and the US and is part of the NASA summer. VLBI observations use up to 16 radiotelescopes simultaneously at different sites Origins programme. Future Origins telescopes around the world. The data are then combined to simulate one enormous telescope, giving include the successor to the Hubble - the the highest resolution available in astronomy. (JIVE.) Next Generation Space Telescope, currently programmed for launch in 2006.

CERN Courier October 1999 13 ELECTROWEAK PHYSICS 200 GeV achieved for 2000

In the last 10 years electroweak, physics has been transformed from a subtle effect into big science. At the forefront of this effort has been CERN's LEP electron-positron collider, which is now celebrating its tenth birthday CERN's LEP electron-positron ring • operating between 45 and 100 GeV per beam.

The news broke in the September issue (p7) that CERN's LEP elec­ with electrons and positrons at 100 GeV. However, the protons in the tron-positron collider was running at 100 GeV per beam (giving a LHC machine, built in the same tunnel, go beyond 8TeV. total collision energy of 200 GeV) and giving very stable conditions. The 1977 LEP study group looked at 100 GeV per beam or more in Some 10 years ago, equipped with room temperature copper a 51 km circumference ring, but, because of technical difficulties radiofrequency cavities, LEP began operating at 45 GeV per beam. and the cost, a study for a machine half the size of LEP-100 was From 1995, superconducting radiofrequency began to be added prepared. In 1978 the study group produced a 22 km ring design and the machine's energy increased initially to 65 GeV per beam, aimed at 70 GeV, and the emerging 1979 design foresaw a 31 km then to 80.5 GeV in 1996 and to 94.5 GeV in 1998. ring with stored beams capable of being taken from an injection While this dramatic boost in collision energy via superconducting level of 22 GeV up to 130 GeV, with an initial operation of 86 GeV. radiofrequency power looks like a latter-day accomplishment, from The ring was subsequently trimmed to 27 km and, as approved by the very outset LEP was foreseen as being capable of attaining at CERN Council in 1981, LEP was optimized for a beam energy of least 100 GeV beams. The pioneer 1976 study group (which 80-100 GeV but with an initial operation phase of up to 55 GeV.The included Burt Richter, visiting CERN from SLAC in Stanford) initial LEP study group at CERN was led by Eberhard Keil, Wolfgang addressed a machine that was designed to achieve a beam energy Schnell and Kees Zilverschoon. Emilio Picasso became project of 100 GeV and a luminosity (which is a measure of the particle col­ director in 1981. lision rate) of 1032/sq. cm/s. Electrons are very light particles, so LEP's initial physics goal was to find and make precision electron rings have to combat losses owing to synchrotron radiation measurements of the Z, which is the neutral carrier of the weak as the beams are bent. To minimize these losses, the LEP circum­ interaction. Using the freshly minted electroweak model, other ference was made as large as possible. Therefore the magnets do experiments in the late 1970s and early 1980s began to hint that not have to be very powerful. the mass of the Z and its electrically charged W companion were Protons, however, do not lose much energy via synchrotron radia­ around 100 GeV. tion and proton rings can be compact, with powerful magnets to Synthesizing the Z in electron-positron annihilations would need bend the beams. As a result, CERN has its 27 km LEP ring running only 50 GeV .per beam, but the W, which has to be produced in

14 CERN Courier October 1999 The footprint of CERN's 27 km LEP electron-positron ring fits between the Jura mountains (left) and Geneva airport (right).

oppositely charged pairs, would need twice as much beam energy. direction. Higgs particles have to be present to make the electro­ Thus LEP had to be capable of producing W pairs. weak theory tick, but the theory can predict very little about them. However, by the time the final LEP design report had been No explicit sign of Higgs particles had turned up by the time the W formulated in 1984, the W and the Z had been discovered at CERN's pair threshold had been reached at 80.5 GeV per beam. However, proton-antiproton collider with masses of around 80 and 90 GeV physicists had another lever to prise open the Higgs door. The inter- respectively.The lattice of magnets, which hold LEP's electrons and consistency of the accumulated electroweak data limits where the positrons on track, was optimized for the 80-100 GeV beam energy Higgs particles can be, even if the particles are as yet invisible. In the range. same way that parallax measurements from two telescopes give a Although the Z had been found, LEP still had the formidable task better fix on a distant star than can be achieved by a single sighting, of making precision measurements of this particle. An electron ring electroweak measurements from different sectors give a sharper that is optimized for running at around 80 GeV per beam is not picture with less room for the Higgs to maneouvre. unduly taxed when running at 45 GeV per beam to produce Z With the electroweak prize at stake, LEP's beam energy was particles. From 1989 to 1995 the four LEP experiments amassed pushed beyond the W pair threshold from 1998. When the beam between them some 20 million Zs. energy is increased from 80 to 100 GeV, the electrons and positrons Meanwhile, work had been under way to ensure that the super­ lose 2.44 times as much energy via synchrotron radiation and these conducting radiofrequency power would be available for the higher- losses have to be compensated for by superconducting power. energy LEP beams - the R&D programme had begun even before That this can be achieved is the ultimate success of LEP's super­ LEP had been formally approved. With sufficient superconducting conducting radiofrequency programme and its attendant cryogenics. accelerating power on board, the four LEP experiments began log­ The continually increasing collision rate (luminosity) at these higher ging the production of W pairs in 1996, and this physics too became energies reflects the foresight of the LEP machine designers, who the subject of precision study. ensured that the ring had all of the necessary beam-handling power As these electroweak data began to pile up, another physics hori­ right from the beginning. The trick was to allow for flexible phase zon beckoned. At the heart of the electroweak model is the mysteri­ advance, which focused the beams more tightly as the energy ous Higgs mechanism, which endows the vacuum with a preferred increased, to combat their natural tendency to increase in size. •

CERN Courier October 1999 15 ELECTROWEAK PHYSICS From Z to ZZ - a decade of electroweak precision

After having carefully amassed some 18 million Z particles one by one over 10 years, the experiments at CERN's LEP electron-positron collider are now producing Zs in pairs.

Exactly 10years ago, experiments %11 at CERN's LEP electron-positron collider saw their first Z particles. Now, with its energy increased from 45 to 100 GeV per beam, LEP can JLfetl produce pairs ofZs. In the event shown here from the DELPHI detector, the first picture shows energetic muons (the green squares are muon signals) and the second shows the showers (jets) produced by a quark pair.

The Z pairs are the latest addition to a physics gallery that was counterpart of the Z, until 1996, when LEP's energy was increased opened 21 years ago when an experiment using a polarized electron sufficiently for experiments to record their first W pairs. beam at SLAC, Stanford, provided the first firm evidence that nature At Stanford this year, David Charlton of Birmingham reported on included a synthesis of weak and electromagnetic interactions. electroweak physics from LEP2 (LEP operating at or beyond the This landmark experiment succeeded in measuring the delicate threshold for producing W pairs). The W mass fix from LEP is interference effects between processes mediated by electro­ 80.35 ± 0.056 GeV, which is now more accurate than the Fermilab magnetic photons and those mediated by the Z (the electrically Tevatron fix and reflects the shifting focus of W physics. Even greater neutral carrier of the weak force). Soon after, Abdus Salam, one of accuracy is obtained via indirect measurements from the latest the architects of the unified picture, coined the term "electroweak". round of neutrino experiments at Fermilab. Five years on, at CERN's proton-antiproton collider, the Z came Using this and other input, electroweak consistency arguments out into the open. In 1989, CERN's new LEP electron-positron col­ strongly hint that the mass of the Higgs particle, which is responsible lider and the SLC linear collider at SLAC were being commissioned for the subtle symmetry-breaking mechanism at the heart of the and the stage was set for a new kind of physics - precision studies electroweak mechanism, is lighter than 300 GeV. of the electroweak interaction using Z particles. At its new energies, LEP is able to probe the interaction of electro­ At the 1989 Lepton-Photon Symposium at Stanford, SLC physi­ weak carriers among themselves, for example via WWZ and WW- cists reported finding 233 Zs. LEP reported 10000 Zs in October. photon mechanisms. (A fuller report of LEP2 physics achievements A decade later, this year's lepton-photon meeting returned to will be published shortly.) Stanford (p6). Morris Swartz of Johns Hopkins, who reported on pre­ Fermilab'sTevatron proton-antiproton collider still enjoys exclusive cision electroweak physics with Z particles, had 18 million Zs to draw coverage of the sixth top quark, which was discovered in 1995. The on, amassed, mainly, by the four LEP experiments from 1989 to latest mass fix, reported at Stanford by Mark Lancaster of Berkeley, 1995, before LEP's energy was increased. The SLC went out in a is centred at 174.3 GeV. Electron-positron machines cannot see the blaze of glory last year (CERN Courier October 1998 p29) and, with top quark directly, but can infer its presence indirectly. The LEP LEP exploring pastures new, these 18 million events will probably electroweak consistency fit gives a compatible top quark mass. remain the bulk of the world's Z physics archive for some time. After 10 years of precision electroweak physics, the Higgs particle From the Z discovery in 1983 until the advent of LEP and the SLC now looms large. However, with LEP's radiofrequency powerhouse in 1989, colliders at CERN and Fermilab enjoyed a monopoly on Z working at full stretch, there is still a chance that LEP could deliver physics.This monopoly continued for the W, the electrically charged the Higgs before the machine is finally switched off next autumn.•

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The Sudbury Neutrino Observatory in Canada has produced its first images of neutrino interactions in its 1000 tonnes of heavy water. The data from this new type of neutrino detector could weight help to pin down the properties of solar neutrinos.

neutrinos from the Sun - an effect known for 30 years - was initially attributed to the innate difficulties of neutrino experiments and of Neutrinos are always compelling physics, estimating the radiative neutrino power of the Sun rather than the The neutrino sessions at this year's neutrinos themselves. In his presentation, Yoichiro Suzuki of Tokyo asked why solar International Lepton-Photon Symposium at neutrino experiments, which were the first to detect neutrino deficits, had not claimed the discovery of neutrino oscillations.The reasons, Stanford gave an up-to-date snapshot. observed Suzuki, were the uncertainty of gauging the solar neutrino flux and the difficulty in providing a unique oscillation solution. Neutrinos, which interact only via the weak force, may be the purest Flux-independent indicators, such as a systematic difference form of lepton and deserved to be in the spotlight at the between the daytime and night-time signal and a spectrum revealing International Lepton-Photon Symposium at Stanford (p6). Neutrino the way that neutrino behaviour changes with energy, would provide physics questions are frequently unresolved and are even contro­ a more reliable indication. However, these were not forthcoming from versial, like Pauli's prediction of a particle that hardly interacts at the pioneer experiments. all. Neutrino physics has lived up to this reputation ever since. Super-K has amassed 825 days of logged solar neutrino data, Last year, data on neutrinos generated by cosmic-ray collisions in and the day-night rates differ by 6.5% (albeit with an error of almost the atmosphere ushered out the old orthodox view that neutrinos 50%) - a possible indication of solar neutrino effects owing to are massless particles. Endowed with mass, the three kinds of neutrino transitions occurring while they pass through the Earth.The neutrinos - electron, muon and tau - are not immutable and can energy spectrum does not look flat. "oscillate" from one kind of neutrino to another. This year the The Sudbury Neutrino Observatory in Canada will soon provide neutrino results presented at the International Lepton-Photon valuable new data on additional reactions of solar neutrinos via the Symposium showed that this view has now firmly taken root. neutral as well as the charged current of weak interactions. The 1998 paradigm shift was the outcome of the release of initial At Stanford,Tony Mann of Tufts covered the atmospheric neutrino data from the 50 000tonne Super-Kamiokande underground sector - centre stage since the Super-K results of 1998. As well as neutrino detector in Japan.The effect - a deficit of muon neutrinos - the Super-K water Cherenkov detector, the Soudan II sampling measured by the Super-Kamiokande detector had been known calorimeter in the US and the Macro muon detector in the Italian since the early 1980s from smaller experiments. However, the Gran Sasso laboratory are also adding their weight. Super-K signal inspired physicists with new 50 000-tonne confi­ The angular distribution of Super-K signals, originally displayed dence. One year down the line this confidence seems complete. in only five angular bins - now extended to ten - clearly show the Atmospheric neutrinos are not alone in oscillating.The dearth of sharp deficit of muon neutrinos travelling upwards, after having

CERN Courier October 1999 19 NEUTRINOS

passed through the Earth before hitting the detector. surveyed the experiment's track record but found no cracks. Neutrino oscillation looks likes it's here to stay, but the nature and Chorus and Nomad at CERN had set out to see the production of parameters of the oscillations have yet to be determined. Studies tau neutrinos from an accelerator-produced beam mainly com­ using neutrinos from reactors and from accelerators are playing a posed of muon neutrinos. Both studies have completed data taking, key role. At Stanford, Luigi Di Leila of CERN was the reviewer. although Chorus has not yet analysed all of the interaction triggers The Chooz (pronounced "Shaw") reactor experiment in France in its emulsion target. With no tau production yet seen, the contours provided key results that limited the possibilities for the disap­ showing the limits on neutrino mass difference and mixing pearance of electron-type neutrinos over a 1 km flight path from the parameters can be extended substantially. reactor to the detector.The Chooz experiment has now completed its A major new player on the neutrino scene will be the MiniBoone mission but another, at Palo Verde in the US, continues to take data. experiment, which uses a beam derived from the Fermilab booster. As for neutrino experiments at accelerators, a long-standing fea­ This should definitively confirm or refute the LSND result. ture has been results from the LSND study at Los Alamos and the To explore the remaining allowed oscillation territory, the emphasis Karmen detector at the UK Rutherford Appleton Laboratory on the also turns to "long baseline" experiments in which neutrino beams appearance, or otherwise, of (anti)electrons from a beam of muon from accelerators travel over several hundred kilometres before (anti)neutrinos.The former "sees" a signal, the latter does not, but reaching the main neutrino target. the two results are not entirely incompatible - the regions accessed The K2K experiment using beams from the Japanese KEK labora­ by the two experiments (and others) do not coincide totally.Thus, the tory and the Super-K detector has now started (p5), while the oscillation signal suggested by LSND cannot be ruled out. Making MINOS study (p6) will cover a longer baseline and use higher-energy this effect consistent with the rest of the neutrino data is highly con­ particles. The KAMLAND experiment in Japan (CERN COURIER April straining, according to Hamish Robertson of Washington in his sub­ p22) will look for interactions from neutrinos emitted by nuclear sequent review of neutrino mass and oscillations. reactors more than 100 km away. A feature of current neutrino dogma is that the bizarre "sterile" With questions unanswered and several projects underway, with neutrinos, which do not react, could sap the power of other neutrino more at proposal stage, and the fact that the implications of the beams as their non-sterile particles oscillate out of sight. Some results are of importance for our understanding of the universe, neu­ physicists are openly sceptical of the LSND result. Di Leila dutifully trino physics will maintain interest well into the next century. •

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The BaBar experiment represents "a new mode of US experiment­ The dedication of the BaBar detector for ation", said Stanford Linear Accelerator Center (SLAC) director Burt Richter at the experiment's formal dedication on 13 August. BaBar is the recently commissioned PEP-II B factory the detector at the heart of the recently commissioned PEP-II B fac­ tory at SLAC, Stanford. Some 50% of the physicist participation and at SLAC, Stanford, showed the increased 40% of the hardware value come from outside the US. international aspect of US particle physics. Physicists habitually use an overstrike to denote an antiparticle. They talk about "p-bars" instead of antiprotons, and "B-bar" as the The keynote antiparticle of a B meson - hence BaBar, better known in certain speaker at the circles as the friendly elephant in the stories by Jean de Brunhoff. formal SLAC research director David Leith explained that BaBar is highly dedication of "non-SLACentric", with a spokesman (David Hitlin of Caltech) who is the BaBar elected rather than appointed. "We went to school at CERN to learn experiment at how to manage large international projects," explained Leith. the recently SLAC, which was established to exploit the 2 mile linear electron commissioned accelerator, is no stranger to major projects. However, the more than PEP-II B factory 600 strong BaBar collaboration is the largest research group that at SLAC, SLAC has ever seen, with physicists from Canada, China, France, Stanford, on Germany, Italy, Norway, Russia and the UK, as well as the US. 13 August was The keynote speaker was director of the US Department of director of the Energy's Office of Research, Martha Krebs, who underlined the role US Department of PEP-II and BaBar in current US particle physics research. After of Energy's the demise of the superconducting supercollider in 1993, a "future Office of visions" panel, chaired by Sid Drell of SLAC, foresaw a US pro­ Research, gramme with significant US participation in the LHC collider at Martha Krebs. CERN. Also included was the SLAC B factory, initially green-lighted in (Diana Rogers, the same wave of legislation that swamped the SSC. SLAC.) Krebs went on to point out that no fewer than 8 of the 10 DOE labs in her portfolio had appointed new directors. She called for leader­ ship during a difficult transition period. In a recent hiccup, a US Senate subcommittee explicitly recom­ mended a reduction in research and development spending for the Next Linear Collider (NLC), an electron-positron machine being touted around the Pacific Rim to attack the next energy frontier. While physicists are gung-ho about the need for such electron- positron machines to explore fully the immediate energy frontier, the move is redolent of the early 1990s disfavour in certain political quarters that eventually torpedoed the SSC. "In staying at the energy frontier," said Krebs, "we cannot count on an orderly progression." "They are not as ready to proceed with the NLC as we are," com­ mented Richter, who stepped down as SLAC director at the end of August. He is succeeded by Jonathan Dorfan, formerly SLAC asso­ ciate director and head of the PEP-II B factory project. Richter becomes chairman of the International Union of Pure and Applied Physics. Krebs paid tribute to Richter's exemplary role as a leader, both at SLAC and for the community. The podium at the BaBar dedication ceremony, with experiment The BaBar dedication fitted nicely into the programme for the spokesman David Hitlin at the microphone. At the event, International Lepton-Photon Symposium at Stanford (p6). • everyone sported a BaBar baseball cap.

CERN Courier October 1999 21 B PHYSICS Physicists focus on quest for Bs

The physics of B particles is a major new focus of world particle physics research. A session at the recent lepton-photon symposium provided a useful overview.

Both SLAC in Stanford and the Japanese KEK Laboratory are begin­ ning physics research with new B factories. The electron-positron annihilations in these colliders are a copious source of B particles, so called because they contain the fifth "beauty", "bottom" or simply "b" quark. The decays of these B particles are expected to reveal new information about CP violation - the subtle symmetry breaking widely thought to be responsible for a Big Bang that was matter-antimatter symmetric, which eventually produced a visible universe composed entirely of matter. The factories - PEP-II at SLAC and KEKB at KEK - use the BaBar and BELLE detectors respectively to study the decays of B particles. This new effort for B physics was an overture for the International Lepton-Photon Symposium in Stanford (p6). Jonathan Dorfan,then SLAC director designate, described the PEP-II and BaBar pro­ gramme. Fumihiko Takasaki of KEK described KEKB and BELLE. However, there are other B physics players. Klaus Honscheid of Ohio State covered the programme at Cornell's CESR electron- positron collider equipped with the CLEO detector. CESR - whose collision rate has continually been boosted - and CLEO - now under­ going its third major facelift - have been working in tandem for some 20 years and have made pioneer contributions to B physics. Warming up on the B touchline is the HERA-B experiment at DESY using the proton ring of the HERA collider. Michael Medinnis of DESY-Zeuthen outlined the detector effort under way en route to scheduled completion next year. Manfred Paulini of Berkeley sketched the B physics potential of the big CDF and DO detectors at Fermilab'sTevatron proton-antipro- ton collider, now fed by the new Main Injector. Also from next year, detector upgrades and collision rate improvements are set to ensure that the Tevatron remains a focus of B physics. Major contributions also come from LEP at CERN. Not described in the Lepton-Photon Symposium presentations but gearing up for The BaBar detector at the heart of the PEP-IIB factory at SLAC, longer-term contributions are the LHCb experiment at CERN's LHC Stanford. collider and the BTeV project at Fermilab. •

22 CERN Courier October 1999 B PHYSICS Hands off

The International Committee fully the new physics that must for Future Accelerators (ICFA) exist will require the LHC plus is a platform for the world an electron-positron collider particle physics community, with energy in theTeV range. particularly where inter­ Just as our present under­ national collaboration on standing of physics at the CD major machine projects is highest energy depends criti­ TO/) concerned. In the aftermath of cally on combining results a recent US Senate recom­ from LER the SLC and the mendation (p21) to reduce Tevatron, a full understanding funding on the Next Linear of new physics seen in the Collider (NLC) - an electron- future will require both types positron machine to attack the of high-energy probes. next energy frontier - the ICFA "Major laboratories around issued the following statement the world are presently con­ iwcivnj after its meeting during the ducting accelerator research CRYOGENICS International Lepton-Photon and development that will Symposium at Stanford (p6): lead to detailed designs of a Manufacturing Line "Scientific panels charged linear electron collider cap­ - Cryogenic Valves with studying future directions able of reaching this energy (Shut-off and Control Valves, for particle physics in Europe, range.The technology being Vacuum Jacketed and also for Japan and the US have con­ developed for this purpose will Cold Box Mounting) cluded that there would be also have applications in other - Special Valves for any Cryogenic compelling and unique scien­ areas of science and technol­ Applications tific possibilities at a linear ogy through new generations (Check-Valves, Pilot Cryogenic electron-positron collider in of intense light sources. A Valves, Relief Valves etc.) theTeV energy range. Such a worldwide group is studying - Bellows Sealed Valves facility is a necessary comple­ the physics at an electron- (up to PN420) ment to the LHC hadron col­ positron collider and the - Cryogenic Transferlines and lider, now under construction detectors needed to observe Couplings at CERN. Experimental results that physics. (Johnston and Multi-Coaxial Couplings) over the last decade from the "ICFA recommends contin­ - Space Cryogenic Components LEP and SLC electron-positron ued vigorous pursuit of the - Custom made Cryogenic colliders, combined with those accelerator research and Components e.g. from theTevatron - a hadron development on a linear col­ Cryostats and Ejectors collider-have led to this lider in theTeV range, with the worldwide consensus. goal of having designs com­ Cryogenic On Off Valve > "The latest experimental plete, with the most reliable manually operated with position '4 results point ever more clearly cost estimates, in a few years. indication and limit switches, to the conclusion that there is We believe that an electron Y-pattern, for cold box mounting fundamentally new physics in collider optimized for the new the energy range just out of physics should be built in a WEKA AG • Schurlistr. 8 • CH-8344 Baretswil • Switzerland reach of existing colliders. At timely way with international Phone ++41 (0)1 939 29 59 • Fax ++41 (0)1 939 29 63 the very least we will find one participation." E-Mail: [email protected] Fur USA und Kanada: PROVAC LTD, POB18411, Greensboro, North Carolina 27419 or more Higgs scalar bosons ICFA is a working Phone (910) 282 6618, Fax (910) 288 3375, E-Mail: [email protected] or other structure that has the subcommittee of the Fur Japan: NIPPON SANS0 CORPORATION same effect as a Higgs boson. International Union of Pure PLANT & MACHINERY DiV., SPACE & CRYOGENIC EQUIPMENT DEPT. 6-2 Kojima-cho, Kawasaki-ku, Kawasaki-City, Kanagawa-Pref. 210, Japan To explore and characterize and Applied Physics. Phone 044 (288) 4063, Fax 044 (299) 4109 E-Mail: [email protected], WWW: www.sanso.co.jp

CERN Courier October 1999 23 CP VIOLATION Why does CP violation

The seemingly obscure phenomenon of CP violation is increasingly being viewed as the key to a deeper understanding of both the behaviour of elementary particles and the Big Bang origin of the universe. Here, John Ellis of CERN explains how far and how deep the implications of CP violation extend.

The visible universe is composed of matter particles - protons, neutrons and electrons - rather than their antimatter partners - antiprotons, antineutrons and positrons. If the Moon were composed of antimatter, then lunar probes and astronauts would have van­ ished in a fireball of energy as soon as they touched the lunar sur­ face. The solar wind and cosmic rays do not destroy us, implying that the Sun and the Milky Way are also made of matter. If there were any region of antimatter within our local cluster of Exploring the untracked expanses of the cosmos and the galaxies, we would be able to see radiation from matter-antimatter microworld - eminent CERN theorist John Ellis. annihilations at the boundaries. Moreover, the cosmic microwave background radiation shows no signs of disturbance by subsequent universe? A possible answer was provided by Andrei Sakharov in annihilation radiation, suggesting that there are no large regions of 1967. He laid out three conditions that would enable a universe antimatter within at least 10 billion light years - and perhaps the containing initially equal amounts of matter and antimatter to evolve whole visible universe. into a matter-dominated universe, which we see today. The Big Bang should have created equal amounts of matter and The first requirement was that the proton - the bedrock particle of antimatter. Why is there now so much of one and so little of the nuclear matter - should be unstable. The second was that there other? CP violation - an obscure effect seen only with certain kinds would be interactions violating C and CR as shown by Cronin and of elementary particles - could provide the answer. Fitch, that would open up the possibility that the universe's initial exact matter-antimatter symmetry could be upset. The third Enter CP violation condition was that the universe would undergo a phase of extremely A recent article by Gerry Bauer ("In hot pursuit of CP violation" CERN rapid expansion: otherwise, matter and antimatter particles, having Courier June p22) set the CP violation scene. In 1964, James equal masses, would be fated to pair up with equal densities. Cronin, Val Fitch and collaborators discovered that the decays of If a cosmological matter-antimatter asymmetry could be built up neutral kaons did not respect the symmetry known as CP - the in this way, all of the remaining antimatter particles would annihilate combination of particle-antiparticle (charge conjugation - C) and later in the history of the universe, leaving behind matter particles mirror (parity - P) symmetry. and radiation, as observed today. It had been known since 1957 that weak interactions violate both Sakharov's landmark paper provided the conceptual framework the C and P symmetries - neutrinos spin left-handedly, whereas their for generating a matter universe, but it has fallen to subsequent gen­ antiparticles (antineutrinos) exist only in right-handed form. Despite erations of physicists to explore specific mechanisms realizing his this maximal violation of C and R it had been thought that they were ideas, opening up some possibilities and excluding others. Key roles always violated together so as to respect the combination CP in this exploration are being played by recent experimental results However, the Cronin-Fitch experiment showed that this could not from CERN and Fermilab, and new data from SLAC, KEK, Cornell, be exactly true. What is the connection between this abtruse DESY and Frascati may soon be making important contributions. property of elementary particles and the matter dominance of the The favoured theoretical framework for CP violation was provided

24 CERN Courier October 1999 matter to the universe?

The kaon decay channel of the NA48 experiment at CERN - the latest study to provide a precision measurement of CP violation.

in 1973 by Kobayashi and Maskawa, who pointed out that CP was soon realized that the minimal GUTs originally proposed would violation would follow automatically if there were at least six quark yield too small an excess of quarks, so the GUT would need to be flavours. Measurements in the neutral-kaon system and elsewhere expanded to produce the amount of matter particles that are are all consistent with this being the only source of CP violation, observed in the universe today: 10"9 of the number of photons. although they leave room for other sources, which inventive theorists It was suggested that the extra CP violation required might also continually propose. generate a neutron electric dipole moment large enough to be detected. (Although a neutral particle, the neutron could contain an GUT feeling asymmetric distribution of equal and opposite positive and negative Also in 1973, Pati and Salam, and Georgi and Glashow, proposed charge.) However, a long experimental campaign currently led by an grand unified theories (GUTs) containing new interactions that experiment at ILL Grenoble limits this to less than 6x 10~26ecm, allowed for proton decay. Such decay would violate the conservation analogous to the Earth's surface being smooth and symmetric to of baryon number-the total number of strongly interacting particles less than 1 urn. minus the number of antiparticles. So far, dedicated searches in By then, theorists had developed new ideas. One idea was that such large underground detectors as Super-Kamiokande have not the strong interactions might also violate CP The fact that this has seen any evidence for this. However, the evidence that they have not been seen led to the postulation of the axion, which might be a found for neutrino masses suggests that interactions that violate component of the universe's dark matter. lepton number (the total number of weakly interacting particles minus the number of antiparticles) do exist.This is another key pre­ Weak washout diction of many GUTs, and may even play a role in generating the The other surprise was that electroweak interactions could also matter in the universe, as discussed later. change baryon number.This does not happen via the exchange of a In 1978, CP violation and GUTs were combined by Yoshimura in a specific particle. Instead it arises from coherent fields with non-triv­ proposal for generating the matter asymmetry of the universe via ial topological properties.These non-perturbative electroweak inter­ the decays of massive particles. His idea was that, if they produced actions provide both a challenge and an opportunity.The challenge a CP-violating excess of quarks in their decays, this would evolve is that they might "wash out" any matter density that is built up by into the matter that we see in the universe today. Unfortunately, it GUT particles. The opportunity is that they might enable the matter

CERN Courier October 1999 25 CP VIOLATION

density to be built up by the electroweak interactions alone. CP violation might be sensitive to subtle effects One way to avoid the weak washout is to have the GUTs generate indicating new physics that might be a net density of leptons, which the additional weak interactions provides a related to a mechanism for gener­ would then recycle into baryons. One such scenario, proposed by uniquely subtle ating the matter in the universe. Fukugita and Yanagida, relies on the decays of heavy right-handed One such experiment is LHCb, neutrinos in the early universe. Some indirect support for this link between which is scheduled to start taking scenario comes from recent experimental hints that the known light inner space, as data at CERN's LHC collider in 2005. neutrinos can mix (oscillate) and have masses, which could be due BTeV, another next-generation B to mixing with such heavy neutrinos. At least some neutrino models explored by experiment, is under consideration for that fit the neutrino data are also able to generate the matter in the experiments in theTevatron.There are plenty of other universe. Another weighty implication of the new neutrino data? opportunities for future experiments As a GUTIess alternative, perhaps the matter in the universe was the laboratory, to probe CP violation and cast light generated when the cooling of the universe triggered a phase and outer space, on the ori&n of the matter in the transition enabling quarks and the W and Z carriers of the weak force pq PvnlnrpH h\/ universe. One is provided by rare neu- to acquire their masses from the Higgs boson? This electroweak db CApiuieu uy tra) kaon decays, for example, pro- mechanism would require the phase transition from a hot universe teleSCOpeS ducing a neutral pion together with a with massless particles to the present state with massive particles to ma " tf th neutrino and an antineutrino or an have been abrupt, so as to meet Sakharov's third requirement. [Measuring ine electron-positron pair.The measure- Unfortunately, the Higgs boson has not yet shown up at CERN's density Of matter ments of direct CP violation in decays LEP electron-positron collider, implying that it weighs more than *n tha n" ore int0 tW0 pions leave room for lar^e about 100 GeV and that the electroweak phase transition was too in me Universe. supersymmetric contributions to CP weak to allow the matter of the universe to be generated this way. violation, which could cast light on However, the door is not yet closed. For example, a supersym- supersymmetric scenarios for the origin of matter. metric scenario, with new "sparticles" partnering the known Another opportunity is the continued search for the neutron particles, might provide a suitable abrupt transition, and also electric dipole moment, which might be able to reach the sensitivity contain additional CP-violating effects that could generate a suitable required to test GUT models for the origin of matter. matter density. These supersymmetric options suggest that LEP, which is now operating at higher energy, might produce a Higgs Future violations boson this year or the next. If LEP is lucky, this could also have In the longer term, there are enticing opportunities to search for CP weighty implications for the universe. violation in neutrino oscillations, which could explore aspects of the models based on the decays of heavy neutrinos. Studies are under CP in the laboratory way on "neutrino factories" based on the decays of muons in storage One of the great attractions of such GUTIess models is the possibility rings (CERN Courier July p22). These provide well defined neutrino that they could be tested in laboratory experiments on CP violation. and antineutrino beams with both electron and muon flavours, which This exciting prospect has been underlined by the recent provide opportunities to search for CP-violating effects in the oscil­ confirmation, by the KTeV experiment at Fermilab and by NA48 at lations of neutrinos and antineutrinos. Looking further ahead, if the CERN, of direct CP violation - the decay of neutral kaons into two problems of controlling the muon beams can be solved, muon col­ pions - first measured by the NA31 experiment at CERN . The mag­ liders could study Higgs bosons in unparalleled detail. nitude of the effect is surprisingly large. Supersymmetric models capable of generating matter in the uni­ Another possible observation of CP violation has recently been verse raise the possibility that the decays of Higgs bosons might reported by the CDF collaboration at Fermilab in the decays of reveal novel violations of CP symmetry. neutral B particles, each giving a J/psi and a neutral kaon. A large CP violation provides a uniquely subtle link between inner space, effect is expected in the Standard Model, and this is the most likely as explored by experiments in the laboratory, and outer space, as interpretation of the CDF data, although a null result cannot yet be explored by telescopes measuring the density of matter in the excluded completely. universe. CP violation in the decays of B mesons is the primary objective of I am sure that this dialogue between theory, experiment and the experiments BaBar and BELLE at the B factories, which are cosmology will culminate in a theory of the origin of the matter in the starting to take data at SLAC in Stanford and KEK in Japan. Their universe, based on the far-reaching ideas proposed by Sakharov in first task will be to seek confirmation of CP violation in the reaction 1967.This would be an achievement comparable in significance to probed by CDF and to search for CP violation in the decays of neutral the emerging theory of the formation of structure in the universe, Bs into pion pairs. based on inflation and dark matter. Microphysics and macrophysics Also in the hunt will be HERA-B at DESY, the revamped CLEO are now yoked together, pulling scientific explorers across the detector at Cornell and experiments at Fermilab'sTevatron collider. untracked expanses of the cosmos. Even if these experiments turn out to agree with the orthodoxy of the Standard Model, there is scope for follow-on experiments that John Ellis CERN.

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The MRS I999 Fall Meeting will serve as a key forum for discussion of interdisciplinary1999 MRS FALL MEETING ACTIVITIES leading-edge materials research from around the world. SYMPOSIUM TUTORIAL PROGRAM Various meeting formats—oral, poster, round-table, forum and workshop sessions—Availabl e only to meeting registrants, several tutorials will are offered to maximize participation. concentrate on new, rapidly breaking areas of research. EXHIBIT 1999 MRS FALL MEETING SYMPOSIA Over 275 international exhibitors will display a full A: Multiscale Phenomena in Materials—Experiments Structure and Electronic Properties of U spectrum of equipment, instrumentation, products, software, and Modeling Dielectric Films on Silicon and Related Structures publications, and services. B: Computational Approaches to Predicting the Optical Amorphous and Nanostructured Carbon Properties of Materials Thin Films—Stresses and Mechanical Properties VIII PUBLICATIONS DESKS NOVEMBER 29- C: Microstructural Modeling for Industrial GaN and Related Alloys A full display of over 600 books, plus videotapes and DECEMBER 3 Metals Processing Frontiers of Materials Research electronic databases, will be available at the MRS BOSTON D: New Advances in Materials Prediction Ferroelectric Thin Films VIII E: Nucleation and Growth Processes in Materials Thin Films for Optical Waveguide Devices Publications Desks. MASSACHUSETTS F: Nanophase and Nanocomposite Materials III Materiols Science of Food— G: Nonlithographic Approaches to Micro- and Nanoscale Processing-Structure-Property Relationships SYMPOSIUM ASSISTANT OPPORTUNITIES Organization HYNES CONVENTION Electrical, Optical, and Magnetic Properties of Organic Graduate students planning to attend the 1999 MRS Fall CENTER H: Molecular Electronics Solid-State Materials V I: Self-Organized Processes in Semiconductor Alloys— Complex Fluids and Polymers Meeting may apply for a Symposium Assistant (audio­ and Spontaneous Ordering, Composition Modulation, and Mineralization in Natural and Synthetic Biomaterials visual aide) position. BOSTON MARRIOTT 3-D Islanding Materials Science of Phospholipid Assemblies COPLEY PLACE J: Advanced Materials and Techniques for Electroactive Polymers JOB CENTER Nanolithography Transport Properties and Microstructure of A Job Center for MRS members and meeting attendees K: Thermal Spray—Materials Synthesis by Thermal Cement-Based Systems Exhibit: will be open Tuesday through Thursday. Spraying Superplasticity—Current Status and Future Potential November 30- L: Fundamental Mechanisms of Low-Energy-Beam- Superconducting Materials—Properties, Crystal Modified Surface Growth and Processing December 2 Chemistry, and Processing M: Interfacial Engineering for Optimized Properties II For additional meeting information. N: Atomic Scale Measurements and Atomistic Models of Magnetoresistive Oxides and Related Materials Epitaxial Growth and Lithography Materials Issues for Tunable RF and Microwave ..or to request a detailed 1999 MRS Fall Meeting Program, contact: 0: Substrate Engineering—Paving the Way to Epitaxy Devices P: Optical Microstructural Characterization of Smart Materials n t n iTT ^ Materials Research Society Semiconductors Materials Science of Microelectromechanical System Q: Advances in Materials Problem Solving with the (MEMS) Devices II MM

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P.O. Box 4 7550 GA Hengelo The Netherlands Phone: +31 74 246 28 53 COSMIC RAYS Looking at cosmic rays with accelerator detectors

Simulation of the atmospheric showers produced by a 100 TeV cosmic iron nucleus (right), a proton (centre) and a gamma ray Large detectors constructed at accelerator (left). Red denotes electromagnetic particles above 10 GeV, labs can also be used in parallel for cosmic- green denotes muons above 10 GeV and black denotes hadrons above 10 GeV. ray studies. Effects measured in distant particle physicists are rediscovering the attractions of natural detectors could be correlated to provide a sources of high-energy particles. While these natural sources provide broader view of particles from the cosmos. energies far beyond those that will be opened up by the next gener­ ation of particle colliders, the event rates are puny in comparison.

When CERN came into being in the early 1950s, a sea change was Cosmic-ray revival taking place in particle physics research. Until then, cosmic rays had There are two primary motivations for this cosmic-ray revival. First, provided most of the basic particle physics discoveries. Accelerators dramatic results from the Super-Kamiokande underground experi­ made their first contributions at Berkeley in 1949, with the Chicago ment in Japan, studying neutrinos produced by cosmic-ray collisions and Carnegie synchrocyclotrons not far behind. In 1953, the in the atmosphere, strongly suggest that the different kinds of neu­ Cosmotron, so named because it was the first accelerator to attain trinos transform into each other- or "oscillate".To exploit these neu­ cosmic-ray energies, began operation at Brookhaven and provided trino possibilities fully requires accurate knowledge of the physicists with the first laboratory-made strange particles. cosmic-ray muon spectrum. With existing data samples mutually At the Bagneres conference in 1953, leading cosmic-ray physi­ disagreeing by 20-30%, more accurate data are called for. cist Cecil Powell, who had been awarded the 1950 Nobel Prize for Second, direct measurements of primary cosmic rays of energies his 1947 discovery of the pion, said: "We have been invaded. The of greater than 1014eV (100 TeV) are impractical. For example, above accelerators are here." 1016eV there is only one particle per square metre per steradian Although many of CERN's first-generation physicists cut their per year. However, the primary cosmic-energy spectrum extends research teeth on cosmic rays, for more than 40 years CERN went beyond 1020eV and there is great interest in the composition, the about building and exploiting its large accelerators, and cosmic-ray energy spectrum and the interaction of the primary cosmic rays with physics took a back seat. nuclei in the upper atmosphere. Knowledge of the cosmic-particle With cosmic rays reporting particles beyond 1020eV - thousands composition above the "knee" (a few times 1015 eV) could shed light of times as high as the highest laboratory energies now available - on how particles are accelerated to such high energies.

CERN Courier October 1999 29 COSMIC RAYS

From ground-based observations of dif- J\]q C0SITliC-r9y progress. STonwar (Tata Institute) described the planned addition of ferent particles (in extensive air showers) a surface air shower array above L3, which will enable the obser­ and from studies of atmospheric scintilla- CO HI ITIU PI Ity vation of energetic muons together with the related air shower. J tion and Cherenkov light, the cosmic-ray \]q§ Ie3med 3 Strom (Arcada), A Bruhl (Siegen) and M Schmelling (Max-Planck community has learned a lot, but many . , Institute) presented the current status of the ALEPH cosmic-ray pro­ mysteries and uncertainties remain. Even 'Ct, DUt many gramme. More than 300 000 cosmic-ray muon events have been with good data, it is difficult to determine UiyStGNOS 8 fid analysed, and good agreement with the KASCADE Monte Carlo sim­ simultaneously a unique primary compo- . . ulations obtained for multimuon events observed in the 16 sq. m sition and interaction model. Uncertainties time-projection chamber for multiplicities (total number of produced Data collected by large detectors at f0main particles) between 2 and 40. However, there are five events with accelerator laboratories would be a valu­ unexpectedly large multiplicities: up to 150 (in some cases with able contribution. With a relatively modest investment, these detec­ additional muons observed in the hadron calorimeter). tors can be exploited for cosmic-ray physics in parallel with, and Other ALEPH studies look at the "decoherence" curve - the coin­ with no loss in efficiency for, the primary mission. cidence rate between two muon detectors as a function of their At CERN's LEP collider, a subgroup of the L3 collaboration has separation, extending beyond 1 km. formed the L3+Cosmics group, using new electronics to enable the Horst Wachsmuth (CERN) proposed looking for muon coinci­ muon spectrometer drift chambers to be read out independently of dences between the four LEP detectors, a phenomenon that should LEP data collection. A blanket of about 200 sq. m of scintillator has not occur for any "ordinary" cosmic-ray interaction in the Earth's been installed over the top three octants of the magnet to provide a upper atmosphere. Such a coincidence, suggested by some earlier reference time signal for cosmic-ray data collection. Under 30 m of cosmic-ray experiments, would certainly require explanation. rock, the cosmic-ray muon threshold for L3 is about 15 GeV. Other major particle physics detector groups are also interested. Elsewhere in the LEP ring, members of the ALEPH collaboration A De Roeck (DESY) discussed the potential involvement of the big are running a pilot CosmoALEPH experiment to look for coincident HI and ZEUS detectors at DESY's HERA electron-proton collider for muons over long distances.This group has examined, together with studies of coincident cosmic-ray muons. With these detectors only the newly established CosmoLEP group, the cosmic-ray data col­ 3 m below ground they could study cosmic-ray muons down to ener­ lected during the ALEPH runs. gies of 2 or 3 GeV, which is of great interest to the atmospheric muon Data archives have revealed a substantial collection of cosmic-ray neutrino groups. muon events. Although the detector is live for only 10% of the time It is also possible, using satellite (GPS) time recording, to look for cosmic-ray particles, this nevertheless adds up over several years for time correlations between cosmic-ray muons at DESY and CERN. to more than a million seconds (about 12 days). Muon multiplicities, etc, have been analysed using sophisticated Future study cosmic-ray simulation programs developed by the Karlsruhe group. M Vallinkoski (Oulu) described a possible new cosmic-ray muon Intriguing events, producing unprecedented numbers of muons, experiment in a mine in Phyhasalmi, Finland. The Centre for have sparked a proposal to study these phenomena in more detail. Underground Physics in Phyhasalmi (CUPP) would deploy a seven- detector array at several vertically aligned depths to study the multi­ Topical workshop plicity, lateral distribution and energy spectrum of cosmic-ray A topical workshop in Sodankyla, about 100 km north of the Arctic muons. Circle in Finland, on 24-29 April and organized by Karsten Eggert of It was noted that major detectors could also be sensitive to point CERN, highlighted the resurgence of interest in cosmic-ray muons. sources of cosmic-ray muons and, using the Moon as a cheap and The Karlsruhe group with its KASCADE detector array has, per­ efficient absorber and the Earth's magnetic field as a spectrometer, haps, the most comprehensive data so far on ground-level air might set a limit on the relative flux of high-energy primary antimat­ showers, which can be interpreted in terms of the primary cosmic- ter nuclei. ray spectrum and its composition. The Chinese IHEP group is particularly interested in seeking evi­ CTaylor (Case Western Reserve) and R Engel (Bartol) looked at the dence for possible cosmic-ray associated weakly interacting mas­ primary cosmic-ray nuclear interaction, noting the uncertainty in the sive particles (WIMPS) in L3. final state particle production at very small forward angles that dom­ Workshop organizer Karsten Eggert discussed other areas of future inates cosmic-ray muon production. study, including working with larger and upgraded detectors. As Even though Fermilab'sTevatron Collider energy corresponds to a noted by Lawrence Jones (Michigan) in his opening discussion, cosmic ray, of about 2 x 1015 eV, interacting with an air nucleon at muon studies with LEP detectors contain both elements of an ideal rest, there are almost no data on forward particle production at experimental programme: practical and useful results, such as the energies above the older fixed-target experiments at a few hun­ absolute inclusive muon spectrum, while at the same time there is dred giga electron-volts. sensitivity to new and potentially exciting discoveries, such as unex­ ALEPH and L3 surveyed their respective cosmic-ray muon obser­ pected muon multiplicities, cosmic-ray point sources, WIMP discov­ vations. H Wilkens (Nijmegen) gave an update on the additions to eries and statistically significant coincidences. Paolo Liperi of Rome the L3 detector and electronics and the muon programme in summarized the attractions of the proposed new programme. •

30 CERN Courier October 1999 COSMIC RAYS

ALEPH provides high resolution After analysing tracking in its central Time Projection Chamber (TPC) in a solenoidal mag­ cosmic muon ALEPH netic field and the large hadron calor­ events, five were imeter surrounding the TPC provides further information about cosmic found with the muons. Precision study of these muons, in highest muon experiments particular of muon bundles, gives vital OenSlty ever Seen, information about the primary cosmic rays and the way in which shower particles are produced in the very forward (downward) direction. The primary cosmic particle comp­ osition around the "knee" of the energy spectrum (4x 1015eV) is go cosmic fundamental input for understanding the cosmic acceleration mechanism that pushes particles to these energies. After analysing cosmic muon events captured by ALEPH in parallel with LEP data-taking and during a special one-week cosmic run, five events were found with the highest muon density ever seen. Some 100 muons hit the sensitive area (16 m2) of the ALEPH TPC. Designed to study man-made electron- The most crowded event showed about 160 muons in half of the positron collisions in CERN's LEP ring, the TPC, the other half suffering data overflow. Extensive simulations using the Corsika program, which was ALEPH detector is also ideal for observing developed by the Karlsruhe group, reproduce the lower muon multiplicities, assuming a primary cosmic particle composition complicated natural cosmic-ray events. ranging from protons up to nuclei like iron. However, the five spectacular events are an order of magnitude above the simulation prediction.They could come from either unusually large air showers, above 1017eV, or fluctuations from lower-energy showers, which could hint at new mechanisms for forward particle production. Charge and momentum determination of the muons in these events, as well as the study of their structure over larger areas, may shed light on their origin. A special cosmic run of ALEPH using the tracking hadron calorimeter extended muon measurements to cover 50 m2. The largest event from this run produced more than 100 muons.

High-multiplicity events To study these intriguing events the CosmoLEP group proposes placing a 200 m2 array of drift chambers beside the ALEPH experiment. With this large array, the rate of high multiplicity events would be increased by a factor of more than a hundred and the muon patterns would give a window on the energy and composition of the primary cosmic particles.The larger samples could also reveal point sources of cosmic particles in the depths of the universe. The underground muon showers that have been seen so far extend over, at most, a few hundred metres.The CosmoALEPH effort covers the barrel of ALEPH's central hadron calorimeter together with several scintillator counter stations installed around the LEP ring near ALEPH, which are up to about 1km distant. This pilot Manifold muons: one of the intriguing cosmic events seen in experiment saw coincident muons in counters that were several the ALEPH detector. hundred metres apart and triggered an idea for a still wider muon search. High-energy primary cosmic-ray particles crashing into the atmos­ The four LEP experiments, equally spaced around the 27 km phere 20 km above our heads initiate large air showers with tunnel, could look for muon correlations over much larger distances. hadrons, electrons, muons and neutrinos. By the time they reach The same approach is being followed at the HI and ZEUS detectors ALEPH, 125 m underground, all of these particles are absorbed at the HERA collider at DESY in Hamburg, which are approximately except for neutrinos and muons above 70 GeV. 2 km apart. •

CERN Courier October 1999 31 COSMIC RAYS L3+C = newtoolsetto study cosmic-ray muons

Also under way at CERN is the L3 experiment at LER which has installed a 200 sq. m screen of scintillator to intercept comic rays arriving from the atmosphere.

At CERN's LEP collider the L3 experiment has installed a blanket of about 200 sq. m of scintillator over the top of the magnet to provide a reference time signal for cosmic-ray data collection.

L3+C, an offshoot of the L3 experiment at CERN's LEP A new muon trigger, readout and data acquisition system have electron-positron collider, has been a "recognized" experiment at been installed, as well as a 204 sq. m scintillator matrix covering CERN since April 1998. It takes advantage of the unique properties the L3 magnet to time the passage of particles. Data are collected of the big L3 muon spectrometer (low energy threshold compared to independently, in parallel with L3 running at LER other underground detectors and unrivalled momentum resolution New results for a variety of fundamental topics in cosmic rays, over a wide momentum range) for accurate measurements of astrophysics and particle physics are expected. The cosmic-ray cosmic-ray muons penetrating 30 m underground. muon momentum spectrum, zenith angular dependence and charge

32 CERN Courier October 1999 COSMIC RAYS ratio are being measured to 1% between 10 their momenta. With exotic events recorded by eV/c+18%*- 28.8 GeV/c+20.% and 2000 GeV, thanks to L3's muon drift cham­ many different experiments, particle momentum GeV/c±3.8%- —4.5 GeV/c±7.3% bers and large magnetic volume. spectra should reveal clues to the processes The results will provide new information on involved. the primary composition of cosmic rays, shower The detector will also intercept some upward development in the atmosphere, and pion and muons (due to particles that have traversed the kaon levels at high energies.These data will also Earth).Time variations could reveal meteorolog­ help us to understand the "atmospheric neu­ ical or sidereal effects. Correlations with events trino puzzle", where an anomalous muon neu­ seen by other detectors are also among L3+C's trino signal seen by underground neutrino L3+C picture of a family of four experimental objectives. detectors is heralded as an indication of neu­ muons. Observing the Moon's muon shadow may give trino oscillations. In particular, the precision a flux limit of primary antiprotons near ITeV - measurements will allow a prediction of the absolute number of the Earth's magnetic field acting as a convenient momentum upward-moving, through-going muons above 10 GeV observed by analyser and the Moon as an absorber of cosmic particles. Super-Kamiokande and MACRO underground. L3+C started gathering data in 1998. Then in early 1999 it Independent apparatus increased its acceptance considerably, achieving an event rate of The collaboration is preparing to install 50 scintillators below the 550 Hz. In addition to providing more reliable data, this extends roof of the L3 access hall (above ground). This air shower array will both the momentum measurement and the angular range. help to estimate the primary energy of some showers associated The detector could reveal bursts of point source signals, and even­ with the muons measured underneath.This apparatus is completely tually gamma-ray bursts, and analyse their associated muons. The independent and runs by itself. Events are correlated via the GPS absence of high energy, upward-moving muons (above a few hun­ satellite clock and a signal in the data acquisition system. dred giga electron-volts) will allow a limit to be set on the neutrino The L3+C experiment already has collected some 900 million flux from active galactic nuclei. Studies of the primary composition events and is expected to run up to the end of the LEP operation of cosmic rays in the "knee" region (near 1015 eV) will be boosted in period next year. The first data were presented at August's a unique way by recording muon "families" and measuring all of International Cosmic-Ray Conference in Salt Lake City. •

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CERN Courier October 1999 33 BOOKSHELF/NEW PRODUCTS

BOOKSHELF Duality and Supersymmetric Theories NEW PRODUCTS edited by D I Olive and P C West, Cambridge High Field Superconducting Magnets by University Press ISBN 0 521 641158 6 (hbk HDF plug-in for Adobe Photoshop Fred M Asner, Oxford University Press, £45/$69.95). ISBN 019 851764 5 (£55). A collection of lectures given in a six-month Fortner Software, experts on the Hierarchical Fred Asner traces the discovery and under­ programme at the Newton Institute in Data Format (HDF) data model, announced standing of superconductivity. This includes Cambridge, with an introduction and guide by the availability of the Power Macintosh HDF the development and manufacture of semi­ the editors.The contributors are M K Gaillard, import plug-in vl.l for Adobe Photoshop. conducting materials, the cooling of B Zumino, J GauntlettJ Eguchi, G W Gibbons, With this plug-in, Photoshop owners can superconducting magnets and their control. A Sen, C Bachas, D I Olive and P C West. access and raster image and data objects Asner looks at beam dynamics and winding stored in HDF files. Photoshop's advanced configurations specific to accelerator magnets CP Violation by G Castelo Branco, L Lavoura annotations, colour manipulation, additional and discusses their design principles using and J P Silva, Oxford University Press, imaging and Web publication features compli­ examples from recent major projects. All of International Series of Monographs on Physics ment the image and data manipulation these magnets have to work under extreme ISBN 0 19 850399 7 (£60). functionality of Fortner Software's data access conditions. It is stressed that the design crite­ A complete theoretical and phenomen- and visualization applications: Noesys, ria are not to be taken lightly. One chapter is ological study of CP violation and the CKM Transform,T3D and Plot. For example, Noesys dedicated to particle physics detectors and matrix, including the implications for heavy and Transform can import many data formats, superconducting magnets for medical appli­ quarks.This is a good reference for physicists including text, binary, SDTS, DTED, GeoTIFF cations. Both are major growth areas. at B factories, but little mention is made of the and FITS, and convert them to HDF, thus pro­ enormous efforts that are going into viding Photoshop users with access to data Pulsars as Astrophysical Laboratories for measuring the phenomenon of CP violation. from sources that were previously Nuclear and Particle Physics by Fridolin inaccessible. Weber, Institute of Physics Publishing ISBN FORTRAN 90/95 explained (2nd edn) by The HDF import plug-in vl.l runs on the 0 7503 03328 (hbk £99/$ 180,682 pages). Michael Metcalf and John Reid, Oxford Power Macintosh, Mac OS 8+ and requires Pulsars were discovered by J Bell and University Press ISBNO 19 850558 2 (pbk). 1 MB of hard disk space. It is compatible with A Hewish in 1967 and were identified as Despite the continual appearance of new Adobe Photoshop versions 3.x, 4.x and 5.0, rapidly rotating neutron stars.The physics of programming languages Fortran, now well into 5.1,5.2.The plug-in can be purchased on line neutron stars - of which there are estimated middle age, soldiers on.This new edition ($49) and downloaded via the Website at to be about one billion in the Milky Way alone summarizes the latest standards. Michael "http://www.fortner.com". For full details, - is covered, along with Strange quark matter Metcalf, now retired, was a longtime member contact Hilary Lewis, tel. (+1) 703 478 0181 - when additional quarks come into play of CERN's Information Technology Division. (103) or e-mail "[email protected]". beyond the "up" and "down" varieties consti­ tuting normal nuclear matter.This physics is Cyclotrons and their Applications 1998 - Model 218 Temperature Monitor also receiving a terrestrial boost with the start Proceedings of the 15th International of the programme at Brookhaven's RHIC. Conference on Cyclotrons and their The eight-channel Model 218 temperature Applications, Caen, France, 14-19 June monitor, Lake Shore's most versatile to date, The Symbolic Universe: Geometry and 1998 edited by E Baron and M Lieuvin, reads up to eight diode or resistance temper­ Physics 1890-1930 edited by Jeremy GANIL, France, Institute of Physics Publishing ature sensors twice each second and displays J Gray, Oxford University Press ISBN 0 19 ISBN 0 7503 0663 7 (hbk £220.00/$400). all of the channels continuously. The Model 850088 2. Cyclotrons 1998 was the fifteenth in a 218 supports diodes, Platinum RTDs and At the Second International Congress of series of international conferences initiated in negative temperature coefficient (NTC) resistor Mathematicians, held in Paris in 1900, David 1959. Cyclotrons are used in basic and sensors. Diode sensors are easily Hilbert presented a list of 23 outstanding applied research, radiotherapy and nuclear interchangeable and provide a wide problems in mathematics that, in his opinion, medicine. Included is a complete list of measurement range (1.4-475 K). Platinum needed to be addressed.The sixth congress existing cyclotrons and their characteristics. RTDs are recommended for high temperatures prophetically called for a greater interplay up to 800 K. NTC resistor sensors are meas­ between geometry and physics. Effective Medium Theory - Principles and ured with constant current excitations for less The bridge from 19th to 20th-century Applications by Tuck C Choy, Oxford demanding applications that require their physics has characterized new physics University Press, International Series of specialized temperature response. insights. Relativity, with its multidimensional Monographs on Physics ISBN 0 19 851892 7. Contact Lake Shore Cryotronics, Inc, Steve spaces, ushered in new developments. Some While not at the cutting edge of funda­ Hoenig, Sales and Marketing, 575 McCorkle of the greatest minds in physics and mathe­ mental physics, effective medium theory is a Boulevard, Westerville, Ohio 43082; tel. (+1) matics focused on these new goals.This is a fruitful way of describing and handling 614 891-2244; fax 614 818-1600; e-mail fascinating collection of papers presented at microstructure at the mesoscopic scale.The "[email protected]"; Internet a 1996 conference at the UK Open University. introduction is by Marshall Stoneham. "www.lakeshore.com".

34 CERN Courier October 1999 PEOPLE

MEETINGS

The 6th International Conference on Materials and Mechanisms of Super­ conductivity and High Temperature Superconductors (M2S-HTSC-VI) will take place in the George R Brown Convention Center, Houston,Texas, on 20-25 February 2000. Contact Centennial Conferences, 4800 Baseline Road, A-112, Boulder, Colorado 80303 USA; tel. 303 499 2299; fax 303 499 2599; e-mail "m2s@centennialconferences. com"; "http://m2sconf.uh.edu".

The 11th biennial NATO Advanced Study Institutes on Techniques and Concepts of High-Energy Physics will be held on 15-26 June 2000 in St Croix, Virgin Islands. It is sponsored by the Division of Scientific Affairs of NATO, the High-Energy Physics Programme of the US Department of Energy, the Elementary Particle Physics Programme of the Japanese ambassador to Switzerland, Mitsuhei Murata (left), at CERN with Peter Jenni, US National Science Foundation, Fermilab, spokesman of the ATLAS experiment for CERN's LHC collider. Florida State University, ITEP in Moscow and the University of Rochester. Attendence is limited to 60 participants.There are no spe­ cial application forms. Any advanced graduate student or recent postgraduate in experimen­ CERN-Asia Fellows and tal high-energy physics interested in attending should submit a letter of application Associates Programme containing a CV and a list of publications. In addition, a letter from a senior scientist (advi­ sor), in support of the application, should also Within the framework of the CERN-Asia Division, 1211 Geneva 23, Switzerland; e-mail be sent to the address below. Although the Fellows and Associates Programme, CERN "[email protected]"; fax +41 22 deadline for application is 1 February 2000, it offers three grants every year to East, South- 767 2750. Applications should reach the is advisable to apply as early as possible. For East and South Asian* postgraduates under Recruitment Service at CERN before further information contact Ms C Jones, Dep­ the age of 33, enabling them to participate in 15 November 1999. artment of Physics, University of Rochester, its scientific programme in the areas of experi­ The CERN-Asia Fellows and Associates Rochester, New York 14627-0171, "http:// mental and theoretical physics and Programme also offers a few short-term asso- www.pas.rochester.edu/ASIinfo.html", e-mail accelerator technologies. The appointments ciateship positions to scientists under 40 who "[email protected]". will be for one year, which might, exceptionally, wish to spend part of the year at CERN or a be extended to two years. Japanese laboratory and who are "on leave of Applications will be considered by the absence" from their institute. Applications are Bottled up CERN Fellowship Selection Committee at its accepted from scientists who are nationals of The operations crews are the unsung heroes meeting on 25 January 2000. An application the East, South-East and South Asian* of high-energy physics, ensuring the delivery must consist of a completed application form, countries and from members of the CERN of the particle goods. A letter of appreciation on which it should be written "CERN-Asia personnel who are nationals of a CERN from the NA48 experiment measuring direct Programme"; three separate letters of refer­ member state. CP violation, CERN Courier September p6, ence; and a curriculum vitae that includes a Candidates are accepted from Afghanistan, thanked all who participated in the provision list of scientific publications and any other Bangladesh, Bhutan, Brunei, Cambodia, of their beams at the SPS synchrotron. While information regarding the quality of the candi­ China, India, Indonesia, Japan, Korea, the pleased to receive thanks, the operations date. Applications, references and any other Laos Republic, Malaysia, the Maldives, specialists said that "the LEP experimenters information must be provided in English. Mongolia, Myanmar, Nepal, Pakistan, the traditionally use another channel to express Application forms can be obtained from the Philippines, Singapore, Sri Lanka,Taiwan, their gratitude (champagne), which is much Recruitment Service, CERN, Personnel Thailand and Vietnam. appreciated in the control room".

CERN Courier October 1999 35 PEOPLE

AWARDS Trieste, Italy, is awarded this year to Giorgio Guggenheim fellowships Parisi of Rome I "La Sapienza". Parisi, who Among those awarded prestigious Shiju-Ho-Sho graduated from Rome in 1970, has made Guggenheim fellowships in 1999 was Michael The Japanese KEK Laboratory director-gen­ outstanding contributions in many areas of Riordan, physics author and assistant to the eral, Hirotaka Sugawara, has received the theoretical physics, including elementary director at SLAC, Stanford. Riordan is also the prestigious Shiju-Ho-Sho (medal with purple particle physics, phase transitions, statistical SLAC correspondent of CERN Courier. He ribbon) from the Emperor of Japan as one mechanics, mathematical physics, string plans to use the award to research and write a who.has made an outstanding contribution to theory, neural networks and disordered book on the history of the US Super­ cultural activity in Japan. His achievements systems. He has worked at the National conducting Supercollider, the construction of have been widely recognized, both in Laboratories in Frascati (Italy), Rome which was abruptly terminated in 1993. theoretical physics and in his management of University, and University of Rome II and I Also awarded a Guggenheim fellowship was KEK, where he has been director-general since ("La Sapienza"). In addition, he has had Bruce Winstein of Chicago, who will be 1989. Under his directorship, KEK has one-year appointments at Columbia and at working at Princeton for the year on an experi­ become one of the major world high-energy the Institute des Hautes Etudes Scientifiques ment led by Suzanne Staggs to detect physics laboratories, with two forefront and Ecole Normale Superieure in France. He polarization in cosmic-microwave background projects: the KEKB B factory and the K2K is the author/co-author of two books and 200 radiation. Long Baseline Neutrino Oscillation exper­ scientific articles and he received the iment. This award is not only a personal Feltrinelli Prize for Physics in 1986, the Gravity Research Foundation Awards for honour but also a recognition of high-energy Boltzman Medal in 1992 and the Italgas Prize Essays physics achievement by a Japanese citizen, in 1993. First prize in this year's Gravity Research and it will help to further particle physics Foundation Awards for Essays went to John research in Japan. Money for string Ellis of CERN, Nikolaos Mavromatos of Oxford Two string theorists - Juan Maldacena of and Dimitri Nanopoulos of Texas A&M for their 1999 Dirac Medal Harvard and Eva Silverstein of SLAC - were paper "Search for quantum gravity" (e-print The Dirac Medal of The Abdus Salam among the 32 recipients of 1999 MacArthur archive gr-qc/9905048), to be published in International Centre for Theoretical Physics in Fellowships. the journal General Relativity and Gravitation.

4*^

Bernd Surrow (left) of Schwabisch Hall, now working on the Opal experiment at CERN, receives the annual PhD thesis prize awarded by the Verein der Freunde and Forderer des DESY (Association of the Friends and Sponsors of DESY) for his thesis on proton structure measurements at A line-up of speakers at a recent users' meeting at Brookhaven for a review, "The AGS the ZEUS experiment at DESY. Presenting Alternating Gradient Synchrotron: Past, Present and Future", chaired by Bill Wallenmeyer, the prize was former DESY and CERN former director of the US Department of Energy's Division of High-Energy Physics. Left to director Erich Lohrmann, head of the right: Mel Schwartz (Nobel 1988) - "The Early Years"; Bill Wallenmeyer ;Sau Lan Wu association, which, by supporting social (Wisconsin) - "J/psi and the Middle Years"; T D Lee (Nobel 1957) - "Theory in the Future; and cultural activities, aims to make DESY Mike Zeller (Yale) - "The Rare K-decay Era"; Bill Mozon (UC Irvine) - "The Future Era"; and more than just a centre of scientific Shoji Nagamiya (KEK) - "Heavy Ions". excellence.

36 CERN Courier October 1999 PEOPLE

Among the participants from CERN at the C N Yang retirement meeting were 1988 Nobel Prizewinner Jack Steinberger and Cecilia Jarlskog. (Cecilia chairs the Nobel Prize Committee for Physics, but not for Quantum choreodynamics - physics chemistry, as wrongly indicated in the June chanteuse Lynda Williams upstage at The solar eclipse at CERN on 11 August. issue on p40. Apologies for the error.) CERN.

UNE HAUTE IDEE DE LENTREPRISE

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CERN Courier October 1999 37 RECRUITMENT For advertising enquiries contact CERN Cowr/errecruitment/classified, I0P Publishing Ltd, Dirac House, Temple Back, Bristol BS1 6BE, UK. Tel:+44 (0)117 930 1026 Fax +44 (0)117 930 1178 Rates per single column cm: Mono £30, Single colour £34, Full colour £36. Please contact us for more information on publication dates and deadlines.

DESY is a physics research laboratory with 1.400 DESY is a physics research laboratory with 1.400 employees and more than 3.000 guest scientists from /)§0TX\ employees and more than 3.000 guest scientists from Germany and abroad. The scientific programme ( DESY Germany and abroad. The scientific programme includes research in particle physics and synchrotron Vy^it/ includes research in particle physics and synchrotron radiation. radiation. DESY invites applications for the position of a DESY invites applications for the position of an Postdoctoral Fellowship in Experimental Accelerator Physics Experimental Physicist for R&D work associated with the superconducting linear electron-positron for the Radiation Protection Group collider project TESLA and free electron lasers in the VUV and X ray regime. At the TESLA Test Facility in Hamburg superconducting cavities of highesThte position entails two main activities: performance are developed, and a linear test accelerator is under • verification of all aspects of radiation protection measures in the existing construction whose present energy of 250 MeV will be gradually increased accelerator systems; beyond 1 GeV. The test accelerator will serve also as a drive linac for a •VU Vplannin g and realisation of such measures for the new TESLA linear free electron laser (FEL) of unprecedented performance. collider and FEL-laboratory projects. The candidate is expected to join the R&D programs aiming at the The applicant will be expected to convincingly represent the importance of development of superconducting rf cavities of ultimate performance, and/orradiatio n protection both within DESY and in public. The chosen candidate the development of high power rf couplers and other auxiliary componentswill. , after an appropriate period, assume the post of radiation protection In addition, an active participation in the commissioning of the test linac angroud p leader with responsibility not only for lab employees but also for the VUV FEL facility is expected. liaison with the relevant authorities. Applicants should have a Ph.D. in physics and be under 32 years of age. Applicants should have a Ph.D. preferably in nuclear or particle physics; Special knowledge in accelerator physics, superconductivity and/or several years of experience in the field of radiation protection; experience microwave technology is highly welcome. with extensive program systems in particular with data concerned with The appointment will be at DESY Hamburg and be initially limited to 3 yearradiatios n protection matters; leadership qualities and the ability to interact with a salary according to federal tariffs (BAT lla). with colleagues; good knowledge of English. Letters of application including curriculum vitae, copies of university The appointment is to a permanent position with a salary according to degrees, list of publications and the names of three referees should be senfederat l tariffs (BAT lb). Letters of application including a curriculum vitae, list to: of publications and the names of three referees should be sent to: DESY, Personalabteilung, NotkestraBe 85, D-22607 Hamburg, DESY, Personalabteilung, NotkestraBe 85, D-22607 Hamburg, closing date: November 30th, 1999 Code-No. 56/99 closing date: November 30th, 1999 Code-No. 87/99 Applications are particulary welcomed from qualified women and handicap­Applications are particulary welcomed from qualified women and handicap­ ped persons as they are currently underrepresented within the workforce. ped persons as they are currently underrepresented within the workforce.

FACULTY POSITIONS in EXPERIMENTAL and THEORETICAL HIGH ENERGY PHYSICS UNIVERSITY OF OKLAHOMA The Department of Physics and Astronomy at the University of Oklahoma invitewes mean the ability to apply theories in particle physics, such as QCD, to the applications for two tenure-track faculty positions to begin in Fall 2000. The experimental situation which will unfold in the next century. Current research positions are intended to be at the Assistant professor level, although in interests of our theoretical group include nonpeturbative quantum field theory, exceptional circumstances a more senior appointment may be possible. quantum chromodynamics, vacuum fluctuation phenomena, quantum gravity, Applicants must hold a Ph.D. degree in physics, and must have the ability toan d the physics of magnetic charge. Physics interests of the experimental group teach effectively at both undergraduate and graduate levels. The potential to include electroweak phenomenology (Higgs bosons, bottom- and top-quark contribute strongly to the existing research program is essential. The applicantphysics,...s ) and phenomenology of QCD. should have postdoctoral experience and research objectives that will enhance the external funding of the High Energy Physics (OU-HEP) group. For the For further information about our department see http://www. nhn.ou.edu. experimental position preference will be given to applicants whose backgrounTdo apply for the experimental position, please write to: Dr. Patrick Skubic, and interests overlap those of the experimentalists in the existing OU-HEP groupHEPE, X Search Committee Chair, Department of Physics and Astronomy, whose current research focuses on colliding beam physics as members of theTh e University of Oklahoma, Norman, OK 73019-0225 DO, ATU\S, and CLEO collaborations. The group has recently made contribution(e-mails : [email protected]). to the DO and CLEO silicon microstrip vertex detectors and to development of the ATLAS pixel detector. Major experimental facilities include a VLSI design and To apply for the theoretical position, please write to: Dr. Kimball A. Milton, testing laboratory, a machine shop, an electronics shop, and excellent computinHEPTg H Search Committee Chair, Department of Physics and Astronomy, facilities supported by a full-time staff physicist. The University of Oklahoma, Norman OK 73019-0225 (e-mail: [email protected]). Initial screening of applicants will For the theoretical applicant the potential to initiate a strong theoretical researchbegi n January 10, 2000 and will continue until the position is filled. Complete program is essential. The successful candidate will be able to interact fruitfullyapplication with s will consist of a vita, publication list, a brief description of research members of both our theoretical and our experimental high energy groups. Wane d teaching interests, and at least three confidential letters of recommendation are seeking a physicist wtth a strong background in phenomenology, by whicsenh t directly to the appropriate search committee chair.

The University of Oklahoma is an Equal-Opportunity Affirmative-Action Employer and has a policy of being responsive to the needs of dual-career couples. Women and minorities are encouraged to apply. Jefferson Lab, located in Newport News, VA, is a world-class scientific laboratory centered around a high-intensity, con­ tinuous wave electron beam, which provides a unique capability for nuclear physics research. Currently, we have excellent opportunities for an Accelerator Physicist and two Accelerator Engineers. In these broad based positions, the successful candidates will work as team members developing innovative solutions towards improv­ ing the performance and capabilities of superconducting accelerators and cavities in support of the Laboratory goals of upgrading the energy of CEBAF, developing an FEL facility, and applications of the superconducting RF technology to other national and international accelerator projects.

ACCELERATOR PHYSICIST (SRF) (Position #AR21 07) Emphasis of the work will be in the area of improvement of performance of superconducting cavities: increasing gradient, reducing losses, and improving consistency in performance. This will include, but is not limited to: understanding of fun­ damental limitations, development of new procedures and processes, cryogenic testing, prototype development, cry- omodule assembly, and testing. The minimum qualifications for this position are a Ph.D. in Physics, Applied Physics, or closely related discipline involving particle accelerators. At least five years experience with superconducting accelerating structures and their applications to accelerators, and familiarity with RF measurement techniques. The candidate must have a demonstrated track record of innovative and significant contributions in the area of SRF technology as applied to particle accelerators. Experience with, and contributions to, other areas of accelerator technology will be a considerable plus, as will be excellent communication skills. While the candidate must be able to work independently under minimum supervision, the ability to work effectively in multidisciplinary teams of physicists, engineers, and technicians is of prime importance. The starting annual salary range is $53,000 - $83,900. For a higher classification, ttie salary range is $66,600-$105,300. ACCELERATOR ENGINEER (Position #AR3116) Emphasis of the work will be in the RF and electronic area (design and development of cavities and RF power coupling schemes, testing, fabrication oversight), but interest and participation in other aspects of the SRF accelerator technology will be encouraged and expected. The minimum qualifications for this position are a Ph.D. in Applied Physics or Electrical Engineering with 3 years experience, or MS in Electrical Engineering with a minimum of 7 years experience in rf acceler­ ator technology, and a strong foundation in classical and accelerator physics are required. The candidate must have a demonstrated track record of innovative and significant contributions in the area of rf technology as applied to particle accelerators, such as: design, development, and commissioning of electromagnetic structures and components, couplers, and rf test stands. Knowledge of, and experience with, electromagnetic design codes is required. Experience with and contributions to other areas of accelerator technology, and in particular superconducting rf technology, will be a consid­ erable plus, as will be excellent communication skills. ACCELERATOR ENGINEER (Position #AR3204) Incumbent will support rapid prototyping of hardware used in superconducting rf-based accelerating systems; clarify desired functional parameters, conceive and evaluate potential solutions via analytical and experimental testing; employ emerging fabrication techniques and novel materials as beneficial to application needs; provide an interface between the design development team and production and mechanical engineering staff; collaborate in integrated system testing and commissioning; identify and implement effective and efficient mechanical design solutions in support of accelerator com­ ponent and systems development; and apply finite-element analysis techniques to optimize mechanical properties, includ­ ing dimensional control under load and thermal gradient, vibrational characterization, thermal conduction, etc. The mini­ mum qualifications for this position are a BS in Mechanical Engineering, Materials Science or related field with a minimum of 3 years experience developing creative design solutions to novel problems. Experience with novel fabrication tech­ niques and materials, UHV components, low temperature materials, unusual mechanical properties, rf hardware and relat­ ed accelerator systems is highly desirable.

The starting annual salary range for the two Accelerator Engineer positions are $53,000 - $83,900. For a higher classifi­ cation, the salary range is $66,600 - $105,300. We are located near Colonial Williamsburg and the Chesapeake Bay. For prompt consideration, please send resume and salary history to: Jefferson Lab, ATTN: Employment Manager, 12000 Jefferson Avenue, Newport News, VA 23606. Please specify position number and job title when applying. An Equal Opportunity, Affirmation Action Employer \ ; ; / RIKEN BNL Ft I KEN BNL Research Center Research Center Brookhaven National Brookhaven National Laboratory Laboratory TENURE TRACK - SCIENTIFIC STAFF POSITIONS STRONG INTERACTION THEORY A research center focusing on the physics program of the RHIC Physics Fellow Positions Relativistic Heavy Ion Collider (RHIC), hard QCD/spin The RIKEN BNL Research Center (RBRC) at Brookhaven National physics, lattice QCD and relativistic heavy ion physics has Laboratory, together with university partners, invites applications for been established by the Institute of Physical and Chemical a program of cooperative fellowships in strong interactions theoreti­ Research Japan (RIKEN) at Brookhaven National cal physics motivated by the experimental program of the Relativistic Laboratory. The members of the center will be Research Heavy Ion Collider to be operating at BNL. Each RHIC Physics Associates (two-year appointments) and RIKEN BNL Fellow will be jointly selected and supported for five years, beginning Fellows (five-year appointments). The Center will play a September 2000, by the Center and one of the cooperating univer­ sities and will hold a tenure track faculty appointment (or equivalent) major role in shaping the spin and heavy ion physics in that university's Physics Department. Each fellow will spend research at RHIC. Frequent workshops are planned. about half time at RBRC and the remaining time at the university. Several positions for theorists in the above categories are Candidates should have a Ph.D. degree in theoretical nuclear or expected to be offered for the fall of 2000. Members of particle physics and be interested in pursuing theoretical research the Center will work closely with the existing high energy within a broad range of hadron physics, such as high energy nuclear theory, RHIC physics, QCD (perturbative and lattice), hadronic spin and nuclear physics groups at BNL. physics, hadronic spectra and their transition matrix elements. Theorists with appropriate backgrounds who are interest­ Scientists with appropriate backgrounds who are interested in apply­ ed in applying for Research Associate and RIKEN BNL ing should send a curriculum vitae, publication list, a brief descrip­ Fellow positions should send a curriculum vitae, publica­ tion of their research interests, and arrange for three letters of refer­ tion list, and arrange for three letters of reference to be ence to be sent to Professor T.D. Lee, Director, RIKEN BNL Research sent to Professor T.D. Lee, Director, RIKEN BNL Research Center, Building 51 OA, Brookhaven National Laboratory, P.O. Box 5000, Upton, Long Island, NY11973 before January 1, 2000. Center, Building 51 OA, Brookhaven National Laboratory, Additional information, including a list of this coming year's partici­ P.O. Box 5000, Upton, Long Island, NY 11973-5000, pating universities, is available by sending an e-mail request to before January 1, 2000. BNL is an equal opportunity [email protected] or by writing to the above address. BNL is an employer committed to workforce diversity. equal opportunity employer committed to workforce diversity. BROOKHAVEN NATIONAL LABORATORY BROOKHAVEN NATIONAL LABORATORY a passion for discovery a passion for discovery www.bnl.gov www.bnl.gov

University of California, Riverside Open Faculty Position in (Pfi Experimental High Energy Physics ECOLL POLYTECH NIQU E The Department of Physics at the University of California, Riverside FEDI:RALE DE LAUSANNE invites highly qualified applicants to apply for a new faculty position in The Swiss Federal Institute of Technology Lausanne (EPFL) invites experimental high energy physics. This is an "open level" position and may applications for three posts of be filled at any academic level including the senior level. The appointment will be effective July 1, 2000. The Department is seeking outstanding can­ Professor of Applied Mathematics didates with exceptional research records and demonstrated excellence in teaching. The successful candidate is expected to establish a leading edge in the Department of Mathematics research program involving graduate students and contribute to department The future professors will be mathematicians with an international reputation, teaching at all levels. In high energy physics the current research programs proven by published work at the forefront of their fields. Candidates from all include OPAL at LEP, D-Zero at the Tevatron and CMS at the LHC. In neu­ areas of applied mathematics are welcome. Specialists in the fields of trino physics, faculty are working on the LSND experiment at Los Alamos probability or statistics, differential geometry, and discrete mathematics or and BooNE at Fermilab. Candidates for this position are required to have a optimization are particularly encouraged to apply A taste and talent for Ph.D. or equivalent degree in physics. Salary will be competitive and com­ multidisciplinary collaboration would be an asset. Teaching will be an mensurate with qualifications and level of appointment. Candidates should important responsibility; the positions demand strong interest and skills in teaching and the ability to direct PhD/advanced research in mathematics. submit a letter of application, a curriculum vitae, evidence of teachng skills and evidence of an outstanding research program. They should also arrange The EPFL is an internationally-oriented technical university which offers to have three letters of reference sent to the Department and be willing to competitive salaries, substantial start-up packages and excellent research and submit additional references on request. Letters should be sent to: teaching facilities. Applications are sought for appointments at the associate or full professor Chair, Search Committee levels. The EPFL strongly encourages women to apply Experimental High Energy Physics Department of Physics Starting date: upon mutual agreement. Please ask for the University of California application form by writing or faxing to: Riverside, CA 92521 Pr6sidence de I'Ecole polytechnique fedeYafe de Lausanne, CE-Ecublens, CH-1015 Lausanne, Suisse, Full review of applications will begin January 17, 2000. Applications fax nr. +41 21 693 70 84. received after this date will be considered on a case-by case basis until the For further information, please consult also URL: position is filled. http.//www.epfI.ch, http://dmawww.epff.ch/, http://admwww.epfl.ch/pres/profs.html The University of California is an Equal Opportunity/Affirmative Action Employer. or http://research.epfl.ch/ MAX-PLANCK-INSTITUT FUR PHYSIK (WERNER-HEISENBERG-INSTITUT)

The Max Planck Institute for Physics in Munich is offering postdoctoral positions for experimental physicists interested in active participation in the experimental research program DIRECTOR. of the institute. The research teams are presently engaged in the following projects: high energy particle physics at LEP (ALEPH) and at ACCELERATOR HERA (H1 and HERA-B); relativistic heavy ion reactions at the SPS (NA49) and RHIC (STAR); dark matter search in the Gran Sasso SYSTEMS DIVISION Laboratory (CRESST); cosmic ray studies, in particular on high energy gamma rays, at La Palma (HEGRA, MAGIC); development and construction of components of ATLAS, and preparation of the LHC ARGONNE NATIONAL physics program. All these experiments offer interesting tasks for young scientists like developments of detector components, data LABORATORY acquisition and handling, and physical analyses, depending on the status of the project. The Accelerator Systems Division of Argonne National Laboratory's Advanced Photon Source (APS) facility is seeking a Division Direc­ The institute offers an appointment for initially two years with the tor to lead that organization's broad spectrum of programs in accel­ possibility for an extension up to a total of 5 years, but not beyond the erator science and technology. The successful candidate will direct age of 35. Applicants should be less than 32 years of age. In case of over 160 scientists, engineers, technicians and support staff in the equal qualification preference will be given to handicapped development, analysis, maintenance, and continued improvement of candidates. The institute encourages especially women to apply. the Advanced Photon Source storage ring and injector systems. In Please send your application including a curriculum vitae, a list of addition, the new Director will oversee continued research related to publications, the name of three referees and the indication of your free electron laser (FEL) technology and the next generation of x-ray research interest, preferably before November 15, 1999 to: sources. Much of the research is carried out at the APS Low Energy UndulatorTest Line, presently configured as a 120nm to 530nm free Max-Planck-lnstitut fur Physik, c/o Ursula Grenzemann electron laser. Fohringer Ring 6, 80805 Munchen Telefon: (089) 32354-299, Fax: (089) 32354-305 The Division Director will be responsible for allocating divisional e-mail: [email protected] resources to meet technical, fiscal, and schedule objectives. Other responsibilities include attracting and hiring new staff members in areas requiring expansion, and preparing written reports and oral presentations to governmental and scientific communities. The Di­ rector will also be expected to resolve problems and conflicts related to accelerator technical design and performance and coordinate solutions with APS Operations.

(Pfl This position requires comprehensive knowledge of electromagnetics, ECOLE POLYTECHNIQJJE electrodynamics, accelerator physics, and accelerator-related tech­ FEDERALE DE LAUSANNE nology, as well as comprehensive knowledge of state-of-the-art accelerator activities around the world. Solid standing in the world­ The Swiss Federal Institute of Technology Lausanne wide accelerator community as evidenced by publications and par­ (EPFL) invites applications for the position of: ticipation in accelerator reviews and conferences is expected. This position also requires strong skills in oral presentation, staff motiva­ Maitre d'enseignement et de recherche tion and organization, and scheduling and integrating diverse tech­ (MER) in Acoustics nical activities. for the Department of Electrical Engineering This level of knowledge and skills are usually attained with a Ph.D. degree or equivalent in physics or engineering and 10 or more years The task of the successful candidate will be to develop teaching and experience in accelerator R&D, design, operation, etc., and research research activities in acoustics, more specifically for the modeling of leadership typical of performance at the Senior Scientist level. acoustic fields (radiation and propagation). He/she will develop innovative research related to active noise control. This activity will take Argonne provides an excellent compensation/benefits package. In­ place within the existing Laboratory of Electromagnetism and Acoustics, terested candidates should forward their resume to Rosalie L. in collaboration with other institutes of EPFL, as well as with other Bottino, Employment & Placement, Box ASD-204809-60, institutions and industries on national and international levels. Argonne National Laboratory, 9700 S. Cass Ave., Argonne, IL 60439 or e- Aptitudes for teaching and project management, scientific excellence, mail to [email protected], or fax to personality and industrial background are major assets. He/she will 630/252-7722. Argonne is an EEO/AA supervise student projects, diploma and doctoral theses. employer.

Starting date: upon mutual agreement. The EPFL strongly invites For additional information, please refer women to apply. Please ask for the application form by writing to Argonne's Home page on the internet: or faxing to: http://www.anl.gov/welcome.html. Presidence de I'Ecole polytechnique f&JeYale de Lausanne, CE-Ecublens, CH-1015 Lausanne, Suisse, fax nr. +41 21 693 70 84. For further information, please consult also URL: http://www.epfl.ch, http://dewww.epfl.ch/, http://admwww.epfl.ch/pres/profs.html or http://research.epfl.ch/ Deputy Computing PAUL SCHERRER INSTITUT Facility Directors

Wry:

Brookhaven National Laboratory (BNL) is seeking to fill two The Experimental Particle Physics Group of the Paul positions, Deputy Computing Facility Director for the Scherrer Institute (PSI) is active in rare decay and exotic Relativistic Heavy Ion Collider (RHIC) and Deputy atom experiments at PSI using the world's most powerful proton accelerator, and participates in high-energy physics Computing Facility Director for US ATLAS. These deputy experiments at CERN and DESY. Applications are invited for a facility directors will hold scientific staff positions in the Physics Department and will share, with the facility director, Research Associate primary responsibility for developing and operating major in Experimental Particle Physics High Energy and Nuclear Physics computing facilities at BNL. These facilities, targeting the experiments of the RHIC The successful candidate will assume a major role in an inter­ project at BNL and the ATLAS experiment at CERN's Large national, medium size collaboration planning a new search for the decay of a muon into a positron and photon (fx -> e + 7), Hadron Collider project, will operate at the Tera-scale of forbidden in the Standard Model. Preferably, the applicant has computation and the Peta-scale of data storage. several years of post-doctoral experience and some back­ The Deputy Computing Facility Director for US ground in project coordination. Knowledge in high resolution, medium energy electron and photon spectroscopy would be ATLAS - Position #MK8726 - will play a principal role in beneficial. developing and implementing the plan required to meet the computing needs of US ATLAS in the field of large-scale For any further information please contact Kurt Gabathuler (tel.+41 56 310 32 51, e-mail [email protected]). high energy physics. This plan will involve the cooperative use of facilities at CERN, at the US Tier 1 center at BNL, and Applications should be sent to: at Tier 2 and institutional centers distributed across the US. PAUL SCHERRER INSTITUTE, Personnel Division, ref.code 1400, CH-5232 Villigen PSI, Switzerland. The Deputy Computing Facility Director for RHIC - More openings: www.psi.ch Position #MK8725 - will play a principal role in evolving and implementing the plan required to meet the ongoing computing needs of RHIC in the field of large-scale nuclear physics. This plan spans the various RHIC experiments, their regional centers and collaborating institutions. UNIVERSITY OF TORONTO

Requirements include a Ph.D. in Physics, at least five years Tenure Track Faculty Position postdoctoral experience in large-scale high energy physics Department of Physics (ATLAS) and nuclear physics (RHIC) projects and associated Experimental Nonlinear or Biological Physics computing activities, and demonstrated leadership, planning The Department of Physics will make a tenure track appointment at the and management skills. Substantial expertise in areas such rank of Assistant Professor with an expected starting date of 1 July 2000. An appointment at a higher rank may also be considered. as UNIX system administration, modern programming tech­ We seek candidates with a Ph.D. in Physics, with proven or potential niques, tools and languages and large-scale data processing excellence in both research and teaching. Our goal is to find a candi­ and storage systems are also required. date with a strong experimental background and an innovative, interdis­ ciplinary outlook. We are interested in the general area of physics far For consideration, please forward your CV and three letters from equilibrium: nonlinear physics (e.g. pattern formation, granular of reference, indicating position #, to: M. Kipperman, media, fracture) or biological physics (e.g. DNA dynamics, chemotaxis). We also invite outstanding candidates working in related areas of exper­ Brookhaven National Laboratory, Bldg. 185, PO Box 5000, imental soft condensed matter physics to apply. Salary will be Upton, NY 11973-5000. For more information about BNL, commensurate with qualifications and experience. please visit our website. BNL is an equal opportunity Applications, including a curriculum vitae, a summary of proposed employer committed to workforce diversity. research and three letters of reference should be sent to: Professor Pekka Sinervo Chair Department of Physics University of Toronto 60 St. George Street BROOKHAVEN Toronto, Ontario, M5S 1A7, Canada NATIONAL LABORATORY The deadline for the receipt of applications and letters of recom­ mendation is 30 November 1999. We urge prospective candidates to visit our home page at http://www.physics.utoronto.ca/. The University of Toronto is committed to employment equity and encour­ ages applications from all qualified individuals including women, members www.bnl.gov of visible minorities, aboriginal persons, and persons with disabilities. CERN COURIER Hamburg Outstation RECRUITMENT 111! EMBL

BOOKING The European Molecular Biology Laboratory (EMBL), an international research organisation with its Headquarters Laboratory in Heidelberg (Germany), Outstations situated in Grenoble (France), Hamburg (Germany) and Hinxton DEADLINES (UK), and a Research Programme at Monterotondo (Italy) has the following vacancy at the Hamburg Outstation:

STAFF SCIENTIST (ref. no. 99/53) November: INSTRUMENTATION The EMBL Hamburg Outstation carries out research in structural biology, making use of the special properties of 15 October synchrotron radiation. Currently, it operates seven beam lines at the DORIS storage ring at DESY. These beam line facilities are used by the International scientific community and for in-house research activities. Presently December: about 500 projects are carried out annually. The EMBL instrumentation group designs, builds and maintains these beam lines. In addition, the group develops and builds instruments for specialised and user friendly applications at these beam lines, in cooperation with the local research groups in X-ray crystallography, small 12 November angle scattering and X-ray absorption spectroscopy. The advertised position will be in the instrumentation group. Applicants should have a Ph.D. or equivalent. Experience in the operation of Synchrotron Radiation Contact beamlines, a background in X-ray optical instrumentation and basic electronic and programming skills are Chris Thomas: requested. The capability to integrate into a multi-disciplinary environment and the willingness to cooperate and provide support are essential. A working knowledge of English is required and the ability to Tel: communicate in German is important. Commencing date: January 2000. Closing date for applications: 1 November 1999 +44 (0)1179301031 Further information can be obtained from Dr. Christoph Hermes, fax: ++49 89902 149; email: [email protected]; www: http://www.embl-hamburg.de. Fax: EMBL is an inclusive, equal opportunity organisation. Applicants should submit a CV, including a description of current professional activities, and names and +44(0)1179301178 addresses of three referees, quoting ref. no. 99/53, to: E-mail: The Personnel Section, EMBL, Postfach 10.2209, D-69012 Heidelberg, Germany [email protected] Fax: +49 6221 387555, email: [email protected]

FACULTY POSITIONS IN PHYSICS TRIUMF University of California CANADA'S NATIONAL LABORATORY FOR Berkeley PARTICLE AND NUCLEAR PHYSICS

Director The Physics Department of the University of California, Canada's national laboratory for particle and nuclear physics is now Berkeley intends to make one or more faculty appoint­ seeking a Director. ments effective July 1, 2000. Candidates from all fields of Located on the University of British Columbia campus, TRIUMF houses physics are invited to apply; however applications in the research facilities which include a 520 MeV H~ cyclotron, and the new radioactive beam facility, ISAC. TRIUMF is Canada's main link to fields of theoretical astrophysics and experimental atomic international laboratories engaged in subatomic physics research, and is physics are particularly encouraged. Appointments at both providing for Canada's contribution to the LHC project at CERN. tenure-track assistant professor and tenured levels will be In addition, TRIUMF supports important programs in Life Sciences, considered. Condensed Matter and other cross disciplinary applications.

The position of Director has a preferred starting date of September 1, Please send a curriculum vitae, bibliography, statement of 2000, and is subject to a five year initial term of Appointment. Additional research interests, and a list of references to: information about TRIUMF, and a description of the Director's position are available at www.triumf.ca/director.html Professor Roger W. Falcone, Chair, Department of Physics, University of California, 366 LeConte Hall The search committee will be meeting to begin its selection process in November 1999, and is now inviting suggestions for suitable individuals, #7300, Berkeley, CA 94720-7300, postmarked by as well as expressions of interest from potential candidates. Tuesday, November 23, 1999. E-mail applications will not TRIUMF is an equal opportunity employer, and asks that all applications be accepted. Applications submitted after the deadline will and nominations be directed to: not be considered.

W. John McDonald, Chair of the Search Committee The University of California is an Equal Opportunity, c/o Department of Physics University of Alberta Affirmative Action Employer. Edmonton, Alberta T6G 2J1 EXPERIMENTAL COSMIC RAY PHYSICS (Pfl University of Utah tCOLt POLYTECHNIQU E FEDERALE DE LAUSANNE The Physics Department at the University of Utah is seek­ ing qualified candidates for a tenure track position in The Swiss Federal Institute of Technology Lausanne (EPFL) invites Experimental Cosmic Ray Physics at the Associate applications for a position of Professor or Full Professor level. We seek candidates with Assistant Professor in strong commitments to both teaching and research. Microstructure Fabrication of Silicon Successful candidates will be expected to take a leadership role in the work of the High Resolution Fly's Eye (HiRes) for the Department of Microengineering experiment and allied efforts, as well as teach undergradu­ The research activities of the new assistant professor will be centered around silicon ate and graduate courses in Physics. processes derived from micro-electronics, in particular the development of new manufacturing processes for micro- and nanostructures, leading to the realization of new microsystems for industrial applications. This position requires a high level of Candidates should submit their curriculum vitae, list of scientific research, characterised at the same time by a high application potential. publications and three letters of recommendation by The assistant professor will contribute to the teaching and the advise of student projects, diploma and thesis work. Candidates should have an excellent October 15, 1999 to: understanding of microfabrication, good people skills, and preferentially an industrial experience. Good capabilities to lead a research team is necessary. Past experience of managing projects in collaboration with industrial .partners is Cosmic Ray Faculty Search Committee advantageous. Department of Physics Applications from women are particularly welcome. Applications are also University of Utah encouraged from people who fulfill the requirements of the Swiss program for 115 S. 1400 E., #201 ensuring the continuity of competent university faculty. Deadline for registration: November 15,1999. Starting date: upon Salt Lake City, Utah 84112 mutual agreement. Please ask for the application form by writing or faxing to: The University of Utah is an Affirmative Action Equal Presidence de I'Ecole polytechnique federate de Lausanne, CE-Ecublens, CH-1015 Lausanne, Suisse, Opportunity Employer. It encourages applications from women fax nr. +41 21 693 70 84. and minorities and provides reasonable accommodations to the For further information, please consult also URL: http://www.epfl.ch, known disabilities of applicants and employees. http://dmtwww.epfl.ch/, http://admwww.epfl.ch/pres/profs.html or http://research.epfl.ch/ UNIVERSITY OF Are you looking for... WISCONSIN-MADISON • Bio/Medical Physicists The Department of Physics, University of Wisconsin-Madison invites • "Rocket Scientists" applications for a tenure track position at the assistant professor level in experimental nuclear physics with the appointment to begin in August, • Electrical Engineers 2000. • Software Developers The appointment may be at a higher rank if qualifications and experience warrant. A Ph.D in physics is required. Commitment to •Technical Editors teaching at the graduate and undergraduate levels is expected. • Technical Sales Engineers Applications from outstanding candidates in all areas of experimental nuclear physics will be considered, but individuals with interests in • Laser Engineers neutrino phyiscs, fundamental interactions and nuclear astrophysics are particularly encouraged to apply. • Subatomic, Nuclear, Particle,

Applicants should submit a letter of application outlining their Astro, High, Medium and qualifications and interests with a resume and publications list, and Low Energy Physicists arrange to have at least three letters of reference sent to Lee G. Pondrom, Chair, Department of Physics, UW-Madison, • Cosmologists. 1150 University Avenue, Madison, WI 53706-1390 by December 1, 1999. The material submitted should provide evidence of teaching For further information and professional skills and the ability to carry out an independent research program. recruitment advice on how to promote your position contact Chris Thomas The University of Wisconsin-Madison is an equal opportunity/affirmative action employer and especially encourages women and minorities to apply. Tel: +44 (0)117 9301031 Unless confidentiality is requested in writing, information regarding the Fax:+44 (0)117 9301178 applicants must be released upon request. Finalists cannot be guaranteed confidentiality. E-mail: [email protected] Faculty and Post Doctoral Positions MECHANICAL PROJECT ENGINEER C.N. Yang Institute for Theoretical Physics (Position #AR3223) Jefferson Lab, located in Newport News, VA, is a world-class scientific The C. N. Yang Institute for Theorectical Physics at the State University of laboratory centered around a high-intensity, continuous wave .electron New York at Stony Brook seeks candidates for postdoctoral positions and beam, which provides a unique capability for nuclear physics research. continues to seek candidates for tenure-track faculty and tenured faculty with anticipated appointment date 1 September 2000. Currently, we have an excellent opportunity for a Mechanical Project Engineer to work in our Accelerator Division. The successful candidate Research fields at the Institute include, but are not limited to, gauge field will provide mechanical engineering support for the Division, serving theory, elementary particle theory, statistical mechanics, supersymmetry, and as project engineer on a variety of assigned tasks. Incumbent will be superstrings. responsible for the design, procurement, and fabrication of parts, instal­ For application instructions please see: lation, and commissioning, and all documentation needed to support http://www.physics.sunysb.edu/itp/jobs and maintain said designs. Additional engineering duties may include If your computer manager cannot provide web access, there is a slower vacuum, pressure vessel, cryogenic, magnet, support structures, and alternative - please email for instructions by auto-reply: water system designs as well as heat transfer and vibration analysis. [email protected] Incumbent must be able to take concepts from physicists and other engi­ neers and turn them into working designs. Must be able to work inde­ If you cannot connect electronically, please write to: CNYITP Search, pendently on involved projects and be able to solve complex problems State University of New York, Stony Brook, NY 11794-3840. where there are limited precedents available. Incumbent may work with Review of applications will resume this fall and continue until the positions one or two designers on individual designs or be responsible for lead­ are filled. ing a group of several engineers and designers on larger projects. The University at Stony Brook is an Equal Opportunity/Affirmative Action The minimum qualifications for this position are a BS or MS Degree in Employer. Applications from women, people of color, disabled persons, and Engineering with at least fifteen years of design experience related to veteran are especially welcome. particle accelerators or the equivalent in education and experience. Familiarity with multiple aspects of accelerator design and theory, including injector design, ultra high vacuum, cryogenics, accelerator diagnostics, magnets, alignment, and superconducting radio frequency cavities and cryostat design. The candidate must also be an expert in one CASE WESTERN RESERVE UNIVERSITY or more of the following: injector design, ultra high vacuum, accelerator diagnostics, materials, welding, and superconducting radio frequency Faculty Position in cavities and cryostat design. Supervisory and/or project management Experimental Particle Physics/Astrophysics experience is also required. The incumbent must have a demonstrated ability to do independent research and proven analytical skills. The Department of Physics at Case Western Reserve University is launching a search for an experimentalist in particle physics/astrophysics, with the possibility of a second position, as The starting annual salary range for this position is $66,600 - $105,300. part of major ongoing growth in this area. These will be tenure track or tenured positions For a higher classification, the salary range is $80,700 - $127,500. We are which may be made at any level commensurate with qualifications. located near Colonial Williamsburg and the Chesapeake Bay. For prompt While significant startup funds are expected, we are likely to focus on candidates who already consideration, please send resume and salary history to: Jefferson Lab, have some outside support for their research program. The successful candidate(s) will join ATTN: Employment Manager, 12000 Jefferson Avenue, Newport News, a growing 'effort in particle physics/astrophysics in the newlyrenovated research facilities of the VA 23606. Please specify position number and job title when applying. physics department. Current experimental efforts include underground dark matter detection, and an experimental program at the Fermilab Tevatron and CERN. The expected start date is An Equal Opportunity, Affirmation Action Employer Summer 2000, but an earlier start date may be possible. Interested candidates should apply to Particle Physics/Astrophysics Search Committee, Department of Physics, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106-7079. Questions can be directed by email to [email protected]. CWRU is an affirmativeaction/equal opportunity employer. CERN COURIER'S FULLY INTERACTIVE WEB SITE IS LIVE... Explore the latest hot topics in particle physics Link to physics sites worldwide

Digest news and features from the latest CERN Courier BfOWS6 through previous issues CERN Search current qualityjob opportunities Bookmark cerncourier.com today

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CERN Courier October 1999 45 Spallation Neutron Source Project

ACCELERATOR ENGINEERS AND SCIENTISTS The Spallation Neutron Source (SNS) Project at the Oak Ridge National Laboratory (ORNL) invites applications for positions in accelerator physics and engineering. The SNS is a Department of Energy joint venture project of five National Laboratories for the construction of the next-generation neutron scattering facility for the United States. The SNS is an approved construction project with Line Item funding starting in FY 1999, and a scheduled completion date in 2005. RF Engineers Will participate in engineering design, fabrication, installation, commissioning, and operations activities related to high power and low-level accelerator RF systems; develop and implement maintenance and improvement programs for reliable operations; and provide technical guidance related to preliminary and critical design plans, engineering change proposals, test plans, and integration issues. > Electrical Engineers Will participate in development of the electrical design for power supply systems, diagnostics, and other electrical components and provide technical guidance related to preliminary and critical design plans, engineering change proposals, test plans, and integration issues. Ion Source Group Leader Will manage and oversee construction, installation, and testing of ion sources and other low-beta transport and acceleration hardware for the SNS. Responsible for technical development activities for front-end accelerator equipment. Will also establish personnel needs, qualifications, and training and technical resource requirements for the Ion Source Group. Successful candidates must have an advanced degree in engineering or physical sciences or an equivalent combination of education and experience. A proven record of leadership of scientific staff required for Group Leader position. Prior experience in construction and operations of large-scale accelerator equipment desired for technical positions. Strong written and oral communication skills and the willingness to work as members of SNS team required. Qualified candidates should submit a curriculum vitae with a list of three or more references to: Selection Committee, Attn P.H. Miller, SNS Project, P.O. Box 2009, Dept. SNS-CERN, Oak Ridge, TN 37831-8218 or e-mail [email protected]. Please reference job title when applying. Applications will be accepted until the positions are filled. For more information visit our internet site at http://www.ornl.gov/sns/

ORNL, a multipurpose research facility managed by Lockheed Martin Energy Research Corporation for the U.S. Department of Energy, is an equal opportunity employer committed to building and maintaining a diverse workforce. SNS SPALLATION NtUTRON SOURCE ^ <"() ^

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