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Printable Version CERN Bulletin Nos 49 & 50 – 7 & 14 December 2011 RP delves underground Summer students, Higgs bosons or something else entirely? The choice is yours t the beginning of my mandate, AI undertook to write a message in each issue of the Bulletin, and I’ve been true to my word. Over the last three years, I’ve spoken about eve- rything from LHC physics to summer student programmes. But now I think the time has come to ask you what you’d like me to write about in my bi-weekly messages to the CERN community. (Continued on page 3xxx) News New life for CERN’s first accelerator 1 A word from the DG: Summer students, Higgs bosons or something else entirely? The choice is yours 1 LHC Report: positive ion run! 2 In this issue #JOBS #CERN - hashtags for your career 3 Muon’s (g-2): The obstinate deviation from the Members of the Radiation Protection Group measure radiation in the LHC tunnel. Standard Model 4 New childcare solution helps CERN’s global community 4 t 7-00 a.m. on 8 The LHC’s winter technical stop is rapidly approaching. As in Astroparticle physics in Europe gets a new December the past years, technical staff in their thousands will be flocking roadmap 5 CERN firefighters have got your back covered 6 ALHC and all of to the underground areas of the LHC and the Linac2, Booster, the upstream accel- Enter FameLab and become the new face of erators will begin PS and SPS injectors. To make sure they are protected from science in Switzerland 7 their technical stop. ionising radiation, members of the Radiation Protection Group e-EPS News: Highlights from the European At 7-30 a.m., mem- will perform an assessment of the levels of radioactivity in the Physical Society 8 bers of the Radiation tunnels as soon as the beams have stopped. Origins: Science inspires Art 8 Protection Group will The Slate Garden 9 enter the tunnel to perform a radiation the tunnel 30 minutes after the beams stop You’ve received a Hallmark E-Card? Delete it! 9 mapping, necessary so that the numer- circulating, the amount of time necessary to Ombud’s corner: A simple confidential discussion ous teams can do their work in complete completely exchange the air in the tunnels. can help 10 safety. “Before we proceed underground, We are always the first ones on the scene.” News from the Library: CERN Bookshop we always check first to make sure that the Christmas sales 10 readings from the induced radioactivity Walking, cycling or riding electric trucks, the Take note 11 monitors installed in the tunnels are all members of the Radiation Protection Group Seminars 14 normal,” underlines Christophe Tromel, the make their rounds of the 45-odd kilometres Meeting at CERN 14 engineer in charge of coordinating radiation of the LHC, SPS, and injection and transfer protection operations for the SPS and LHC tunnels. With their meters they continually accelerators. “Normally, we are able to enter measure the ambient radiation level and Published by: record the readings for all machine compo- The European Organization for Nuclear Research - CERN nents. It takes eight people working one- 1211 Geneva 23, Switzerland - Tel. + 41 22 767 35 86 Printed by: CERN Printshop © 2010 CERN - ISSN: Printed version: 2077-950X (Continued on page 2) Electronic version: 2077-9518 www.cern.ch/bulletin RP delves underground (Continued from page 1) and-a-half days to survey the 27 kilometres on 5 and 8 December. Most of the under- In 2010, the number of trips to the under- of the LHC tunnel. ground portion of the LHC will be open to ground facilities during the winter technical the Radiation Protection Group members stop numbered in the tens of thousands. “We use two types of detector to measure half an hour after the beams stop circulat- This year, the tunnels of the world’s biggest the radiation: a scintillation detector and ing, but a few areas will not be opened until accelerator will once again witness a very a Geiger counter. If the reading from the several hours later. The SPS and its transfer large number of interventions. first detector is above 0.5 μSv per hour*, tunnels will be mapped later, between 12 we change to the second, which is better and 14 December. * The level of radioactivity measured around suited to measuring higher levels of radia- CERN is some 0.1 μSv per hour. tion,” explains Nadine Conan, the engineer Once all of the measurements have been in charge of coordinating radiation protec- taken, the Radiation Protection Group will Anaïs Schaeffer tion operations for the LHC and HiRadMat draw up a “radiation map” for the under- experiments. “And when we approach one ground facilities and put up signs marking of the more radioactive points (of the order the most highly radioactive points, so that More information about radiation protec- of several millisieverts per hour), for exam- a visual overview of the radiation levels in tion at CERN can be obtained at: ple an injection, extraction or collimation the area can be rapidly obtained. “For the region, we fit the Geiger counter with a LHC, the radiation maps change from one espace.cern.ch/hse-unit/ special “Teletector” probe that allows us to year to the next,” says Nadine Conan. “They remain at a safe distance from the radiation are affected by various factors, namely the The radiation classification of the LHC tun- source.” increase in intensity, the operation mode, nels can be consulted at: and technical modifications carried out on The upstream accelerators (Linac2, Booster the accelerator.” www.cern.ch/rp-lhc-rad-class-new/ and the PS) will be the first to be mapped, LHC Report: positive ion run! (Continued from page 1) he peak lumi- The current LHC ion run has been progressing very well. The Summer students, Higgs bosons nosity in ATLAS first fill with 358 bunches per beam - the maximum number reached 5x1026 T-2 -1 for the year - was on Tuesday, 15 November and was followed or something else entirely? cm s , which is a The choice is yours factor of ~16 more by an extended period of steady running. The quality of the than last year’s peak beam delivered by the heavy-ion injector chain has been Next year will not be short of subject of 3x1025 cm-2s-1. The excellent, and this is reflected in both the peak and the matter. We’ll have the final word on integrated luminos- integrated luminosity. the Standard Model Higgs, discussions ity in each of ALICE, about the long-term future of the ATLAS and CMS is now around 100 magnets situated near to Point 3. The LHC, and the development of global inverse microbarn, already comfort- cryogenics recovery and the cool-down particle physics. For those of you ably over the nominal target for the run. of the link took until Wednesday after- based at CERN, local concerns might The polarity of the ALICE spectrometer noon. The warm-up of the link required be of interest: how are we developing and solenoid magnets was reversed on some revalidation tests of the magnet our relationship with our neighbours, Monday, 28 November with the aim of circuits, and beam was finally back early and what plans do we have in mind for delivering another sizeable amount of Thursday morning. the Prévessin site? These are just some luminosity in this configuration. of my thoughts. I’m sure you’ll have In the following days, there will be a many others. On the whole, the LHC has been behav- luminosity calibration exercise using ing very well recently, ensuring good Van der Meer scans. There will also be Whatever you’re interested in, drop a machine availability. On Monday even- some machine studies related to future line to [email protected] with ing, however, a faulty level sensor in the performance improvements. Otherwise, your suggestions. Although I doubt cooling towers at Point 4 caused the the accelerator teams are looking forward I’ll be able to respond to them all, I loss of primary cooling water for a short to the end of the run on Wednesday, 7 will answer the most popular requests time. This disturbed the operation of the December. during the course of the year. For my cryogenics system, and one knock-on final message this year, I’ll be report- effect was the warming of a 500m super- Mike Lamont for the LHC Team ing on highlights from the December conducting link between a feed-box and Council meeting. Rolf Heuer 2 – 7 & 14.12.2011 #JOBS #CERN - hashtags for your career ot long ago, Last year, CERN’s HR Department leapt ahead of the curve in recruitment experts, the HR Department jobseekers had recruitment techniques by moving into the social media scene. organised a day-long round-table seminar. Dubbed the “accidental conference”, the Nbut two tools Their success is in the numbers, with applications for CERN jobs they could use to find seminar became a smash hit in the recruit- work: a red pen and increasing significantly. ment industry before it had even begun. a recent newspaper. “As soon it was announced, we started Nowadays, recruitment services are going fessional lives,” says Michel Guye-Bergeret, receiving a remarkable amount of feedback,” right up to their virtual doorstep: posting CERN Recruitment and Sourcing specialist. says organiser Catherine Nederman from announcements on Twitter, Facebook, the HR Department. “In the end, we had LinkedIn, and other social media spheres. As a result of the new strategy – of which over 50 participants attending – includ- The CERN Recruitment Service launched social media is key – applications for CERN ing the Head Recruitment Officers from their social media profiles in October 2010, positions have increased.
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