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Posts Tagged ‘CERN’

Visit of the ATLAS experiment at CERN: Behind the scenes of the search for the Higgs particle

Saturday, December 24th, 2011

In the last weeks the international press was reporting about the first results in the search for the Higg particle at CERN. The infrastructure behind the the LHC experiment in Geneva is impressing in all respects. A large number of technicians and researchers is working around the clock assuring that the infrastructure is working.

In fact the infrastructure is not located only in Geneva but is scattered all around the world. A very powerful grid of supercomputers allows to analyze the huge amount of data being produced.

CSCS is also contributing to the experiment by running a Tier-2 cluster used by Swiss particle physicists. Last October we have been invited by our physicists colleagues to visit where the data we are analyzing is coming from. We visited CERN and in particular the control room for the ATLAS experiment and the facility used to test the magnets used to accelerate the particles.

In addition we have also visited the CMS monitoring/shifters room, the LHC monitoring room, the (formerly) Heavy Ions initial accelerator that is now the first circular accelerator after the linear one in the beginning, and the beginning of everything, where the small bottle of hydrogen is.

CERN Accelerator Complex

Since this is Christmas time, we decided to put almost the full length of our visit at CERN. The movies are only recommended to people really liking physics and technology and that do not get bored too quickly…

In the movies you will have the chance to see what is happening behind the scenes at CERN:

  • The plenary room where all the important announcement are made
  • The “couloir des pas perdus”
  • The ATLAS building from outside
  • The ATLAS control room with scientists and technicians working in front of their control monitors
  • The CMS satellite control room
  • The data canter of CERN with thousands of servers
  • The first node of the modern WWW infrastructure used by Tim Berners Lee (a NeXT workstation with a small hand written label “This machine is a server. DO NOT POWER DOWN!!”)

We would like Marc Goulette (ATLAS visit) and Szymon Gadomski (magnet testing facility visit) for their availability as all our colleagues at CHIPP supporting our work.

Enjoy and meet again next year on this blog.

ATLAS Experiment

Magnet Testing Facility

Videos: The Physics and Experiments at the LHC

Friday, June 11th, 2010

CSCS is operating an HPC system for the Swiss Institute of Particle Physics (CHIPP), which is used to analyze the data from the Large Hadron Collider (LHC) experiment at CERN.

CSCS asked CHIPP to organize an internal one day workshop to present the physics, the experiments and the accelerator at the LHC as well. The morning session was mostly dedicated to a general introduction of the LHC experiment and particle physics. The afternoon session was dedicated to a description of the experiments (CMS, ATLA, LHCb) that are relevant for CSCS.

CSCS has been impressed by the presentations given by CHIPP collaborators. In a very clear way they introduced us to the world of particle physics and of modern colliders and detectors. We are very happy and honored to be able to share with you the recordings of the presentations. They give us an insight in one of the most challenging experiments ever done on Earth, with the largest instrument created on this planet.

We start by publishing the first three introductory presentations of the morning that give an impressive overview on LHC and particle physics. You have in any case to have a look to the first presentation of Prof. Christoph Grab (ETH Zurich) introducing us in the world of particle physics. Then Szymon Gadomski (University of Geneva) explains the LHC experiments and their properties. Finally Michele Weber (Laboratorium für Hochenergiephysik-Universitaet Bern) explains what accelerators are and how they work.

To view the presentations you need Quicktime. Just click on the picture or follow the link underneath for download options (e.g. for you iPhone).

Particle Physics at LHC – an overview

Christophorus Grab (Eidgenossische Technische Hochschule Zurich/ETH (ETH))

  1. The Standard Model of particle physics (SM)
  2. The LHC physics program
  3. Why do we want it
  4. What do we want and hope to measure
  5. Why does it take some time to do this

(more…)

Phoenix PhaseC Upgrade Passed Acceptance Test

Wednesday, March 31st, 2010

CSCS is happy to announce that  Phoenix PhaseC Upgrade passed today the acceptance test. Phoenix is a HPC system run by CSCS used by the researchers of the Swiss Institute of Particle Physics CHIPP to analyze the data from the LHC experiment at CERN.

The upgrade has been delivered and installed by Sun and will double the computing and storage capacity provided by the previous system (also from Sun). The main characteristics of the new cluster are:

  • 96 Sun X6275 compute nodes with in total 768 cores running at 2.56 GHz (Intel E5540)
  • 7.6 TFlops peak performance
  • Lustre 115 TB usable space with a 7.6 GB/s write speed used as scratch
  • 10 Thors X4540 with480 TB total space (plus 672 TB Thumper recycled from PhaseB) used to store experiment data
  • Infiniband QDR used as interconnect

In the next days the system administrators at CSCS will migrate the middleware from phase B to C. PhaseC should be fully operational on Montay, April 19th. You can follow the next steps of the upgrade on twitter: http://www.twitter.com/phoenix_cscs

The Acceptance Protocol being signed by Dominik Ulmer (General Manager, CSCS) and Klaus Landl (Account Manager, Sun)

Part of the project team posing in front of the PhaseC system.

Today we also had the handover of the system responsibility from Fotis (right on the next picture) to Pablo. We thank Fotis for all the excellent job made so far. He has helped make Phoenix into a great cluster during these last 18 months, together with Jason and Riccardo, making it challenging for others to achieve the same quality. Pablo has an extensive GRID background and has been working with us for two months, during which time he has learned the daily procedures at CSCS-LCG2 grid site and is ready to succeed Fotis as system lead.

CERN: LHC research programme gets underway

Tuesday, March 30th, 2010

Today has been a special day here at CSCS for the HPC Co-Location Services team: We were following with crossed fingers the first collisions of the LHC collider at CERN. And everything went well! We are very proud with the cluster Phoenix of CHIPP to contribute as Tier 2 to the analysis of the large amount of data that will be produced by CERN.

Here below you may see a screenshot of the live broadcast of this morning.

And here below you may read the press release of CERN.

Geneva 30 March 2010. Beams collided at 7 TeV in the LHC at 13:06 CEST, marking the start of the LHC research programme. Particle physicists around the world are looking forward to a potentially rich harvest of new physics as the LHC begins its first long run at an energy three and a half times higher than previously achieved at a particle accelerator.

“It’s a great day to be a particle physicist,” said CERN Director General Rolf Heuer. “A lot of people have waited a long time for this moment, but their patience and dedication is starting to pay dividends.”

“With these record-shattering collision energies, the LHC experiments are propelled into a vast region to explore, and the hunt begins for dark matter, new forces, new dimensions and the Higgs boson,” said ATLAS collaboration spokesperson, Fabiola Gianotti. “The fact that the experiments have published papers already on the basis of last year’s data bodes very well for this first physics run.”

“We’ve all been impressed with the way the LHC has performed so far,” said Guido Tonelli, spokesperson of the CMS experiment, “and it’s particularly gratifying to see how well our particle detectors are working while our physics teams worldwide are already analysing data. We’ll address soon some of the major puzzles of modern physics like the origin of mass, the grand unification of forces and the presence of abundant dark matter in the universe. I expect very exciting times in front of us.”

“This is the moment we have been waiting and preparing for”, said ALICE spokesperson Jürgen Schukraft. “We’re very much looking forward to the results from proton collisions, and later this year from lead-ion collisions, to give us new insights into the nature of the strong interaction and the evolution of matter in the early Universe.”

“LHCb is ready for physics,” said the experiment’s spokesperson Andrei Golutvin, “we have a great research programme ahead of us exploring the nature of matter-antimatter asymmetry more profoundly than has ever been done before.”

CERN will run the LHC for 18-24 months with the objective of delivering enough data to the experiments to make significant advances across a wide range of physics channels. As soon as they have  “re-discovered” the known Standard Model particles, a necessary precursor to looking for new physics, the LHC experiments will start the systematic search for the Higgs boson. With the amount of data expected, called one inverse femtobarn by physicists, the combined analysis of ATLAS and CMS will be able to explore a wide mass range, and there’s even a chance of discovery if the Higgs has a mass near 160 GeV. If it’s much lighter or very heavy, it will be harder to find in this first LHC run.

For supersymmetry, ATLAS and CMS will each have enough data to double today?s sensitivity to certain new discoveries. Experiments today are sensitive to some supersymmetric particles with masses up to 400 GeV. An inverse femtobarn at the LHC pushes the discovery range up to 800 GeV.

“The LHC has a real chance over the next two years of discovering supersymmetric particles,” explained Heuer, “and possibly giving insights into the composition of about a quarter of the Universe.”

Even at the more exotic end of the LHC?s potential discovery spectrum, this LHC run will extend the current reach by a factor of two. LHC experiments will be sensitive to new massive particles indicating the presence of extra dimensions up to masses of 2 TeV, where today?s reach is around 1 TeV.

“Over 2000 graduate students are eagerly awaiting data from the LHC experiments,” said Heuer.  “They’re a privileged bunch, set to produce the first theses at the new high-energy frontier.”

Following this run, the LHC will shutdown for routine maintenance, and to complete the repairs and consolidation work needed to reach the LHC’s design energy of 14 TeV following the incident of 19 September 2008. Traditionally, CERN has operated its accelerators on an annual cycle, running for seven to eight months with a four to five month shutdown each
year. Being a cryogenic machine operating at very low temperature, the LHC takes about a month to bring up to room temperature and another month to cool down. A four-month shutdown as part of an annual cycle no longer makes sense for such a machine, so CERN has decided to move to a longer cycle with longer periods of operation accompanied by longer shutdown periods when needed.

“Two years of continuous running is a tall order both for the LHC operators and the experiments, but it will be well worth the effort,” said Heuer. “By starting with a long run and concentrating preparations for 14 TeV collisions into a single shutdown, we’re increasing the overall running time over the next three years, making up for lost time and giving
the experiments the chance to make their mark.”

LHC First Physics: Today Live Webcast

Tuesday, March 30th, 2010

Today marks the start of the LHC research programme with the first attempt for collisions at 7 TeV (3.5 TeV per beam).

Webcasts are available until 18:15 (Central European Summer Time – CEST). The main webcast will include live footage from the control room for the LHC accelerator and from the control rooms of the four main LHC experiments: ALICE, ATLAS, CMS and LHCb.

Follow also on twitter http://twitter.com/cern