After a comfortable night in the CERN hostel, our group breakfasted at Restaurant 1 before meeting with Dr Andy Buckley a researcher from the University of Glasgow, working on the ATLAS experiment at the LHC.

Andy gave us an overview of how the collisions between the high energy protons in the LHC give rise to other short-lived particles, which are detected by their interactions with different layers of the detector. He went on to explain the particular types of interactions which provide evidence of the Higgs field and Higgs boson, the existence of which was jointly verified by the CMS and ATLAS experiments at CERN in July 2012.

ATLAS montage

Andy was keen to encourage us all to ask questions and finished his talk by encouraging us to get in touch if we had any further questions. We hope to be able to organise and online Q&A session in the coming weeks.

After Andy's session we walked across campus to meet Mick Storr, CERN's Head of Education and Outreach, who lead us through a session on one of the earliest particle detectors - the cloud chamber.

Invented in the early 20th century by Scottish physicist CTR Wilson (for which he won a Nobel prize in 1927) a cloud chamber produces trails of liquid droplets in a super-saturated vapour when interactions with particles occur. This effect was used by many other physicists in the early 20th century to observe and identify a number of particle interactions, many of whom went on to win Nobel prizes.

Cloud chamber notes


Despite many attempts to photograph and video the trails we could see being produced by cosmic rays interacting with the vapour in the cloud chambers, we were unsuccessful. However Rebecca promised us all she would send out kits for smaller cloud chambers, so that we could try again once we return to our schools.

After Mick's session, we had a quick lunch before we were taken to the facilities housing the Linear Accelerator (LINAC) and Proton Synchrotron (PS). Our guides Michela and Klaus explained each stage of the system that performs the first stages of accelerating protons for the LHC.



Our tour included a viewing of the famous 'bottle of hydrogen' that we were told provides all of the protons required to keep the LHC running.

bottle of hydrogen

We were also shown the smallest of the accelerators at CERN, the Low Energy Ion Ring (LEIR), where the first anti-atoms were produced. Anti-atoms the the anti-matter equivalent of atoms, composed of an anti-proton and a positron in the case of the anti-hydrogen produced at LEIR. The LEIR system would fit easily into most school games halls, and has a square form with rounded corners. The linear parts of the ring accelerate the particles in a straight line, while the rounded corners house the magnets which cause the particles to travel in a curved path.


Next we were taken to the CERN control centre (CCC) where the group was talked through the various systems that are overseen from the facility. We were also informed of the procedures for shutting down the LHC rings by 'dumping' the protons - a process designed to take place within the time it takes the beams to make three circuits of the ring.

beam dump

group CCC

Our next stop was the Alpha Magnetic Spectrometer (AMS) facility. The AMS experiment was part of the payload on the last ever NASA space shuttle mission and was installed on the International Space Station (ISS) in 2011. AMS was built to detect cosmic rays, antimatter and dark matter. The AMS facility is staffed around the clock, receiving and analysing data sent from the orbiting experiment.


After visiting the AMS facility came possibly the highlight of the whole trip to CERN - a visit below ground at point 5 on the LHC - the Compact Muon Solenoid (CMS) site. Our guides, both of whom were approaching the end of their time at CMS as part of their PhD research, gave us a brief history of the construction and installation of the experiment at the site, and of the operation of the detector.

group at CMS


After a quick safety talk and issuing the group with passes and hard hats we were taken 80 metres below ground level to see one of the computer facilities which evaluates the data gathered from each event within the CMS experiment in order to keep the data for analysis or discard it. Passing through this facility we ventured further down to the actual detector, which was being overhauled during the shut down of the LHC.


Although we had been told many times during our visit about the scale of the LHC  - the 27 km ring and the four main experiment sites - standing next to the CMS detector was genuinely awe inspiring. The students made the most of their visit, asking lots of questions of our guides before heading back to ground level and returning to the main CERN campus for dinner.

After a bite to eat we ventured into Geneva for the evening for a spot of sight-seeing and a go at Mick's 'Treasure Hunt' quiz. Two hours of touring the streets of Geneva took us to 'Le Jet d'Eau' - a spectacular water feature at the edge of Lac Léman, which shoots a spout of water straight up into the air to a height of around 100 ft (30m).

the jet

At the end of a very, very busy day, our slightly soggy and quite tired group boarded the tram and returned to the main CERN campus for a well needed sleep.