by Ladislas Clatot. Published: 04 March 2011

I’m Ladislas Clatot and I am fourteen. I’m a student from the college Jeanne d’Arc in Gex and I had four days of work experience at CERN last week.

On the first day, I had to make an access card because it is mandatory, as CERN is a secured site. After that, I went with Paolo Martinengo to Point 2 where the ALICE Experiment is installed. Paolo is the Run Coordinator and also the project leader of one of the 17 sub-detectors of the ALICE Project. With him, I discovered the Alice Control Room, where physicists and engineers monitor the running of the experiment, They are on shift 24/7.

The ALICE Collaboration

Ladislas Clatot - who visited CERN for work experience

All the people speak English with each other and yet they’re of one hundred different nationalities. They work hard because the experience restarted last Sunday. They plan tests for the coming two weeks and, then, they’ll begin collisions of protons.

On the same morning, I visited with Alex Grigore and Giuseppe Simonetti the counting room of the Data Acquisition Project. It’s a room where a lot of computers register all the data from the experiment at a very high rate of 1 Gbit/second. The computers do not have keyboards and mice, only hard disk storage inside large cupboards.

The data is verified in the control room, transferred to the large CERN computing centre where it is stored and then distributed around the world with the “Grid” for the data analysis by the physicists who are not based at CERN. At the entrance of the counting room, I had to take a badge, which register the level of radiation. This is a preventive measure.

Back in the control room, one physicist explained me that in the ALICE Time Projection Chamber (TPC), many instruments register and transfer all the information from the collisions, from the detector to the control room where the shifters look for the most interesting physics events.

The following day, Despina Hatzifotiadou, the Outreach Coordinator, tested with me the master class exercise. It’s an exercise which uses the data from collisions of protons, visualized on a computer. I searched for strange particles, which are detected by the experiment. I have found this exercise very easy and very interesting.

On Tuesday, I had a meeting with Yves Schutz, physicist and the deputy ALICE spokesperson. Yves explained me the composition of a proton or a neutron, made of 3 quarks which are kept together by gluons (strong force). An atom is formed of one nuclei (proton or neutron) and its electrons. Yves has explained to me the main questions CERN wants to answer:

  • What’s the nature of the primordial matter and dark matter?
  • What’s the difference of the matter and the antimatter and where is the antimatter gone?
  • From where comes the mass of particles?

On Wednesday, I visited the gas workshop with Patrick Carrie. Gas is one of the most used detection tools to trace particles inside detectors. Patrick told me that CERN is one of the main users of gas in the world.

For my last day, Antoine Junique has shown me some electronic chips. Many hours of hard work are necessary to create one of these little chips. Antoine explained me that the design is first generated and tested on a computer, and only after is the chip created. We can find these electronics in all our phones, computers, etc… I am surprised by the fact that it takes so long to develop such small technologies.

My conclusion: I think all the people who are working in CERN are passionate about physics and they love to show us their knowledge. CERN is like a small town where all the people work hard and love it!!!! I would like to thank Julie Hadre for her support during these 4 days.