Student Visit to CERN

This summer holiday I went on a trip to Geneva in Switzerland. The aim of the trip was togo and see CERN, a physics institute on the French-Swiss border but also to explore thetown. The journey to Geneva took 13 hours and I managed to get us from Paris Gare duNord to the Gare du Lyon. However, the highlight was definitely when we went through themountains.

The day we went to CERN started with a 20 minute tram ride across Geneva to the Frenchborder in Meyrin where the facility is located. The first thing we did when we arrived was
buy some gifts and souvenirs of our visit in the CERN shop in the reception: t-shirts,
badges and a CERN pen for school. We checked in for our booked tour, but before itstarted, we were allowed to visit the Microcosm. This a free exhibition explaining the roles
of the detectors in the Large Hadron Collider and how they work. It also gave us an idea ofthe scale of the equipment and just how big it is. This was done by building a quarter sizereplica of the detector, and using two huge mirrors to reflect the remaining three-quarters
into the wall and floor. This meant that you could stand on the mirrored floor and besuspended directly alongside the detector. We also saw a cloud chamber which is amachine that shows how electrons move around in a vacuum. The virtual tour guided us
around the exhibition by using life-sized screens with video recordings of physicists from
around the world. Finally, we saw actual pieces of the colliders in the museum withexplanations of what they do; silicon chips that scan collisions in the Large Hadron Collider
(LHC).
We then headed back to the main entrance to meet up with our tour guide. Firstly, we allwatched an introductory video which explained the different things we would be looking at.
Then, the group was split into two and we headed off to the first stop, ATLAS, (A ToroidalLHC Apparatus), which is the main detector for the LHC. We walked across CERN to thebuilding we would be looking at and we watched a film about the ATLAS detector which is
25 metres high, 25 metres wide, 47 metres long and weighs 7000 tonnes. The film was
very informative and in 3-D which I have only seen a few times and which made it easier tounderstand. It included everything you need to know about ATLAS and the specifics ofhow it functions. It also covered one of the other detectors, CMS, (Compact MuonSolenoid) that has similar aims but uses different magnet-system designs. Following that,
we were allowed to see the actual control room for the detector along with the actualphysicists and analysts that work there. They gave a more in-depth presentation andexplained how the LHC scans the particles. They showed us this by displaying diagrams ofthe particles from the LHC itself.

The second part of the tour involved a long walk across CERN. It also occurred to me thatwe were walking above the tunnel which was 50-175 metres below us and houses the27km Large Hadron Collider itself. When we got to the next building, we went into a hugeroom with the Cornell Electron Synchrotron, the first particle accelerator they built. Thewhole room was turned into a very good presentation that used clever lighting andprojector placement to show how it was built and used over the years until it was
discontinued. This presentation was probably my favourite thing about CERN. It told us
about the history of CERN and the different landmark discoveries and breakthroughs
which I had not heard before. Finally, as we left the building, we saw a detailed timelinealong the walls of the different breakthroughs and constructions at CERN in relation toother things of note in history, for example the moon landing in 1969 and the invention ofthe World Wide Web, by Tim Berners-Lee in 1989.

That completed our tour, so we walked back to the CERN entrance and across to theUniverse of Particles. This is a permanent exhibition in a giant wooden sphere-shapedmuseum. It is dark and feels like being in space. It makes you realise that we are justparticles in a vast universe and we can further understand the universe by studying them.

Apart from CERN, I did many other things in Switzerland. I went on two cruise trips on theLac Leman, and on two sightseeing tours of Geneva and visited the vivarium (a zoo for
reptiles).

The first little open-air bus tour took us through the old town. We saw St Pierre Cathedralwhich was in amongst other buildings. The tour also took us through the Parc des Bastions
where I saw the Reformation Wall monument which is 100 metres long and has lots ofstatues of Protestants from Europe in it. The wall is within the site of the University Genevaand is also part of the old city walls in the Parc near where we saw people playing giantchess. The other tour took us to see where many international organisations are: UnitedNations with all the flags outside, the World Health Organisation, the World TradeOrganisation and many others.

On the boat cruises, we sailed right next to the Jet d'Eau which is one of the tallest
fountains in the world. It can pump out 500 litres of water per second to 150 metres high. Itwas amazing to see Mont Blanc in the distance with snow on even though it was so hot. Atthe Vivarium we saw crocodiles being fed rats and even got to touch a young crocodile.
We saw a venomous snake being fed and how they differ from a non-venomous snake.

On the final day, we visited the Natural History Museum which had hundreds of differentanimals from piranhas to gorillas. Also, there was a section on human history and theevolution of man as well as many multi-coloured crystals that you wouldn't have even
guessed existed.

I had such a good time in Switzerland. Just being at CERN makes you feel like you are atthe centre of physics where something might be discovered at any time. It is hard tobelieve you are actually there.

I would like to thank the school for helping me get to see and do all these things.

Thomas Wadasck