ALICE Prepares to Pinpoint Muons
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I n t e r n at I o n a l J o u r n a l o f H I g H - e n e r g y P H y s I c s CERN COURIERV o l u m e 47 n u m b e r 10 D e c e m b e r 2 0 07 ALICE prepares to pinpoint muons COSMIC RAYS LHC FOCUS ANNIVERSARY Auger finds source A muon spectrometer T D Lee: 50 years after of UHE particles p5 for hot quark matter p 30 parity violation p35 CCDecCover.indd 1 14/11/07 14:37:57 Ocean Optics Spectrometers Combine Forces Instant Measurements from 200-2500 nm Measure Solar Irradiance 200-900 nm Our QE65000 is the spectrometer for measuring solar irradiance from 200-900 nm. This scienti.c grade spectrometer has a TE-cooled detector, resulting in high stability measurements independant of ambient influences. 1 QE65000 + Measure Solar Irradiance 900-2500 nm Our NIR256 is the spectrometer for measuring solar irradiance from 900- 2500 nm. The InGaAs linear array detector is TEC-cooled and deliver high sensitivity and stable operation in the near infrared. 1 NIR256 NEW! = Analyse Solar Irradiance 200-2500 nm Our Spectrasuite Software will allow the user to operate one or more spectrometers as if he is operating just one piece of equipment, increasing the user-friendliness of measuring solar irradiance from 200-2500 nm. 1 SpectraSuite Complete Solar Irradiance Equipment Our wide ranges of accesories like cosine correctors, integrating spheres and mixed fiber bundles will complete your solar irradations measurement system. +31 26 319 05 00 • www.oceanoptics.eu • [email protected] 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 for January and August. The views expressed are not necessarily those of the CERN management. Editor Christine Sutton CERN CERN, 1211 Geneva 23, Switzerland E-mail [email protected] Fax +41 (0) 22 785 0247 Web cerncourier.com Advisory board James Gillies, Rolf Landua and Maximilian Metzger Laboratory correspondents: COURIERo l u m e u m b e r e c e m b e r V 47 N 10 D 20 07 Argonne National Laboratory (US) Cosmas Zachos Brookhaven National Laboratory (US) P Yamin Cornell University (US) D G Cassel DESY Laboratory (Germany) Ilka Flegel, Ute Wilhelmsen EMFCSC (Italy) Anna Cavallini Enrico Fermi Centre (Italy) Guido Piragino Fermi National Accelerator Laboratory (US) Judy Jackson Forschungszentrum Jülich (Germany) Markus Buescher GSI Darmstadt (Germany) I Peter IHEP, Beijing (China) Tongzhou Xu IHEP, Serpukhov (Russia) Yu Ryabov INFN (Italy) Barbara Gallavotti Jefferson Laboratory (US) Steven Corneliussen JINR Dubna (Russia) B Starchenko KEK National Laboratory (Japan) Youhei Morita Lawrence Berkeley Laboratory (US) Spencer Klein Los Alamos National Laboratory (US) C Hoffmann White dwarfs collide p11 Listening to gravity p17 Pief Panofsky 1919–2007 p45 NIKHEF Laboratory (Netherlands) Paul de Jong Novosibirsk Institute (Russia) S Eidelman News 5 NCSL (US) Geoff Koch Orsay Laboratory (France) Anne-Marie Lutz Pierre Auger Observatory pinpoints source of mysterious highest-energy PSI Laboratory (Switzerland) P-R Kettle cosmic rays. Neutrino mixing at Daya Bay. Robert Aymar seals the final Saclay Laboratory (France) Elisabeth Locci Science and Technology Facilities Council (UK) Peter Barratt main magnet interconnection. LHCb installs its fragile precision detector. Produced for CERN by IOP Publishing Ltd Second LHC transfer line passes beam test with flying colours. Opera IOP Publishing Ltd, Dirac House, Temple Back, Bristol BS1 6BE, UK takes first photographs. J-PARC accelerates protons to 3 GeV. 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Marketing executive Chinh Dinh Advertising A global network listens for ripples in space–time 17 Tel +44 (0)117 930 1026 (for UK/Europe display advertising), The Virgo and LIGO gravitational-wave detectors combine forces. +1 215 627 0880 (for North American display advertising), or +44 (0)117 930 1196 (for recruitment advertising); e-mail [email protected]; fax +44 (0)117 930 1178 EPS conference sets the scene for things to come 21 A report on the 2007 meeting in Europe’s biennial conference series. General distribution Courrier Adressage, CERN, 1211 Geneva 23, Switzerland. E-mail [email protected] 25 In certain countries, to request copies or to make address Cockcroft’s subatomic legacy: splitting the atom changes, contact: Looking back 75 years to the first accelerator-based physics experiment. China Keqing Ma, Library, Institute of High Energy Physics, PO Box 918, Beijing 100049, People’s Republic of China. ALICE gets ready to pinpoint muon pairs 30 E-mail [email protected] Germany Veronika Werschner, DESY, Notkestr. 85, 22607 How to build a muon spectrometer to study hot quark matter. Hamburg, Germany. E-mail [email protected] Italy Loredana Rum or Anna Pennacchietti, INFN, Casella Postale T D Lee: a bright future for particle physics 35 56, 00044 Frascati, Rome, Italy. E-mail [email protected] UK Mark Swaisland, Chadwick Library, Daresbury Laboratory, Symmetry and particles, 50 years after the discovery of parity violation. Daresbury, Warrington, Cheshire WA4 4AD, UK. E-mail [email protected] The drip line: nuclei on the edge of stability 37 US/Canada Published by Cern Courier, 6N246 Willow Drive, St Charles, IL 60175, US. Periodical postage paid in St Charles, IL, Dave Morrisey describes the challenges of neutron-rich isotopes. US. Fax 630 377 1569. E-mail [email protected] POSTMASTER: send address changes to: Creative Mailing Faces and Places 40 Services, PO Box 1147, St Charles, IL 60174, US Recruitment 47 Published by European Organization for Nuclear Research, CERN, 1211 Geneva 23, Switzerland. Tel +41 (0) 22 767 61 11 Telefax +41 (0) 22 767 65 55 Bookshelf 55 Printed by Warners (Midlands) plc, Bourne, Lincolnshire, UK © 2007 CERN ISSN 0304-288X Cover: Work on installation of the tracking chambers for the muon spectrometer in the ALICE experiment at the LHC (p30). (Photo by Antonio Saba for CERN.) CERN Courier December 2007 CCDecContents.indd 3 14/11/07 14:27:42 THE BEST! 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Using the world’s largest cosmic- –120 ray observatory, the Pierre Auger Observatory 120 (PAO) in Argentina, the team of 370 scientists –30 from 17 countries has found that the sources of the highest-energy particles are not distributed uniformly across the sky. Instead, the results link the origins of these mysterious particles to the locations of nearby galaxies The celestial sphere in galactic coordinates (Aitoff projection) showing the arrival that have active nuclei at their centres (Pierre directions of the 27 highest-energy cosmic rays detected by the Auger Observatory.