The community of particle physicists has been eagerly waiting for the first run of the proton beam in the heart of the outstanding 27-kilometer LHC instrument. On Wednesday, September 10, 2008 several seconds before the beam was injected into the ring, the tension was palpable not only at the CERN (European Organization for Nuclear Research) in Geneva, but also in the laboratories across the world that are involved in this amazing adventure. For some, it was the realization of an idea, which was born back in 1981. For others, it was the possibility - why not say guarantee - of making major discoveries in the upcoming years. The most extraordinary thing was that all these men and women from many different countries are united by a common drive - a thirst for knowledge.
9:37 a.m. - A Flash Signals Beam Passage
Admittedly, the LHC is a mammoth instrument - just think, a 27 km-diameter ring, buried at a 100-meter depth under the French-Swiss border, through which two proton beams (7 TeV power each) are circulating, they must crash into each other and produce gigantic collisions at specific points of the ring where cutting edge detectors called ALICE, CMS, LHCb and ATLAS are installed. However unlike our image-based society where, more often than not, everything useless is overblown in the media in a vain attempt to fill the void, at the LHC the requisite oversized technology is played down. For instance, at 9:37, a mere flash signaled the passage of the proton beam hailed by the applause of everyone following the first warm-up run. Here no special effects were needed to mask a lack of scenario. There was only the director's cut, as the specialists call it, shot by shot without any trappings, somewhat like great films where every image has a precise meaning.
Each point that was passed was greeted with excited cheers. Granted, for a layman seeing men and women getting excited about a passing beam, albeit a proton beam, materialized by a point of light may seem baffling. Yet, this point of light was the outcome of thousands of hours of hard work, high level brainstorming, tight harnessing of the imagination, and the harbinger of many more similar efforts to come. Understanding this made the men and women's enthusiasm contagious while the beam continued on, successively passing through the four LHC detectors, including the Atlas and CMS giants.
10:26 a.m. - The Beam Completes its first Run
Atlas (A Toroïdal Lhc AppartuS) is 46 meters long, has a 25-meter diameter, and weighs 7,000 tons. It is the largest of the four LHC experiments. Its has three main components: an inner tracker, a calorimeter, and a muon spectrometer. Its main task is to track the illustrious Higgs boson. One hundred and sixty-seven laboratories from 37 different countries (including France), viz., about 1,800 physicists and engineers designed and built the gigantic instrument. The CMS (Compact Muon Solenoid) is barely smaller, i.e., length: 21.5 meters, diameter: 15 meters, and weight: 12,500 tons, making it the heaviest experiment. It also has different layers with a tracker system, an electromagnetic calorimeter and a hadron calorimeter. It will also be looking for the Higgs boson, or even for new particles such as supersymmetric particles, or for additional dimensions of space. No fewer than 2,000 physicists and engineers from 183 institutes in 39 different countries, including France, were involved in developing and assembling the CMS.
At 10:26, applause broke out again at the CERN but also at numerous scientific venues across the planet. The beam injected into the LHC some fifty minutes earlier had just successfully completed its first tour. Make no mistake, this was but a warm-up. However, in a few weeks when the machine will be completely ready, two proton beams will be launched at high speed in opposite directions. The resulting collisions will generate an infinity of particles of all kinds. No fewer than one billion collisions per second are expected, i.e., an information rate equal to 20 simultaneous phone calls for each human being living on Earth!
Unsurprisingly, the IT linked to the LHC will have to accomplish major feats to process the data fast enough to select the one collision among ten million that will be likely to reveal new phenomena. The physicists estimate that the famous Higgs boson, if it exists, should only appear in one out 10,000 billion collisions. At this pace, the LHC detectors should only record one per day!! So, yes, everything is huge, but actually it's the right size for exploring an energy range of up to 14TeV. There is no useless razzle dazzle - intelligence suffices unto itself. At the LHC, it is on the move and ready to blaze trails to new frontiers.
