CERN visit for M2 students
A visit to CERN was arranged for our M2 students by Prof. Alexandre Zabi, a member of Laboratoire Leprince Ringuet (LLR) and of the CMS collaboration, who brilliantly guided us through several of the high-energy physics facilities.
We first got a glimpse of CERN's early history thanks to an exhibition around the very first accelerator built at CERN, the 600 MeV synchrocyclotron (SC), which has recently been opened to visitors.
The second step was the visit of the LHC magnet test facilities (SM-18), where Alexandre explained us the impressive technical challenges that had to be faced in order to design and build the 15 meter-long superconducting dipole magnets (producing a magnetic field of about 9 tesla) which serve to guide the proton and ion beams on their circular trajectory in the LHC. He also described their delicate test phase and their maintainance, partly performed in this very hall.
Our group in the hall of the SM-18 test facilities.
Next, Alexandre led us through the experiment he is working on, the Compact Muon Solenoid detector (CMS). Thanks to the winter shutdown, we could go down to the cavern which accommodates the detector (situated 100 meters underground), currently under maintainance.
...and the same group in front of the CMS detector, open for maintainance. This "compact" detector is "only" (!) 15 meters wide and 21.6 meters long, for a weight of about 14000 tonnes.
We then turned to two smaller-scale experiments.
We first saw the control room of the Alpha Magnetic Spectrometer (AMS), a particle physics detector installed on the International Space Station aimed at better understanding our Universe by precisely studying the properties of cosmic rays, searching for antimatter, dark matter, etc...
We then went to the "Antimatter factory", which hosts the Antiproton Decelerator (AD). The latter is a fundamental element in the process of producing the antimatter, whose properties are then studied in dedicated experiments.
Finally, we proceeded to the computer center, where we learnt about the technical challenges posed by the processing and the storage of the huge amount of data produced by the high-energy physics experiments.