Landing A Last Minute Spot On The CERN Tour

Had I not been able to snag a last minute spot on the CERN tour, I would’ve check the MAMCO, the International Red Cross + Red Crescent Museum and/or the Palais Nation. But as luck would have it, I was able to reserve a spot. Again, so much easier when you’re one person.

The CERN tours are free – all you have to do is register online. CERN opens its dates 15 days in advance at 830am CET and only until they reach half capacity (12 people out of 24 on the tour). They’ll release the remaining half of the capacity 3 days in advance at 830am for booking.

Since the CERN tours are so popular, spots can be booked out minutes after opening, so you either have to be flexible of dates, make sure you’re online for 830am or check back periodically for cancellations.

With only 2 full days in Geneva (and one of those days I went to Morges and Tolochenaz), I was sure I wasn’t going to get in, but one cancellation spot opened up and I snagged it – pronto.

CERN is located on the Swiss and French borders and is the world’s largest particle physics research centre. It’s mandate is to study composition of matter and improve our understanding of the universe.

It’s also home to the world’s most powerful accelerator, the LHC (Large Haldron Collider), which runs underground between Geneva and the Jura Mountains. The LHC studies the origin of mass, dark matter in the universe, antimatter, extra dimensions and the primordial state of matter and runs 24/7.

Our group was led by physicist and tour guide, Shang Liang. He gave us a brief introduction to CERN, had us watch a video on CERN’s history inside the decommissioned synchrocyclotron (SC), led us through the facilities to the operations centre, had us watch another video and ended the tour at the universe of particles exhibit, all while answering our questions along the way. The tour took about 2 hours in total.

PS – These tours do not include any underground visits.

Here’s a timeline of CERN milestones:

1957 – synchrocyclotron (SC) – the first accelerator of CERN (0.6 GEV)
1959 – proton synchrotron (PS) – the world’s mos powerful accelerator (30 GEV)
1976 – super proton synchrotron (SPS) – the world’s most powerful accelerator (400 GEV)
1983 – antiproton-proton collider – discovery of the W and Z bosons, the carriers of the weak force
1989 – large electron-positron collider (LEP) – 200 GEV collision energy for precision tests of the standard model
2008 – large hadron collider – the world’s largest scientific instrument (14,000 GEV collision energy)

Many important achievement were made; some of them being rewarded with the Nobel Prize

drift chamber which revolutionized particle protection by Georges Charpak
cooling of particle beams by Simon van der Meer
discovery of the carriers of the weak interaction by Carlo Rubbia
existence of the Higgs Boson confirmed by Peter Higgs + Francois Englert
world wide web (www) created by Tim Berners Lee while working at CERN

Being in the decommissioned synchrocyclotron reminded me of my trip to Triumf, UBC’s national laboratory for particle and nuclear physics. After walking on top of a huge ass magnet, I swear, Sean and I felt a little off afterwards – physically. I have to admit, I wasn’t sure if I would feel weird walking around at CERN, but in the end, no strange feelings.

The synchrocyclotron is an obsolete machine today. It was retired in 1990 after 33 years of service and was opened in 2015 after the 5 metre concrete wall was removed. It’s no longer radioactive. If the machine was still running, no one would be allowed to go underground due to the magnets and radiation.

Other info and facts I picked up during the CERN tour:

CERN is made up of 22 member states and employs 11,000 scientists made up of 100 nationalities
CERN is 22 metres from french border
Israel was the first non-European country to join CERN
GeV = giga electron volt
The movie Angels + Demons has footage filmed onsite at CERN and gives an idea of the scientists work environment (not creating antimatter to use as a weapon against the Vatican)
Fun fact: old vintage TVs or cathode ray tube TVs operate like particle accelerators, like a mini version of the LHC.

We headed outside so our tour guide to show us a model of what the LHC accelerator tube looked like. If the LHC was to be built on the surface, CERN would have to build a concrete tunnel to enclose it and minimize any risk. The colossal LHC is made up of 1,002 magnet pieces and housed in a 27 kilometres tunnel. Depending on where it is, the tunnel can be up to 150 metres underground. (closer to France, it’s buried under 150 metres of rock; closer to Lake Geneva, it’s at 100 metres)

Particles fly at the speed of light in this vacuum by being accelerated or decelerated. The vacuum box uses helium to cool everything down to -271.3°C degrees (or 1.9 K) and takes 5 weeks to do it. On the flip side, it takes 5 weeks to heat it back up. The tube contracts when cooled down to 1.9 K, which means a difference of 18 metres.

We headed back inside to learn about the ATLAS experiment at the LHC. ATLAS stands for A Toroidal LHC ApparatuS and is the world’s largest general-purpose particle detector. It is an enormous cyclindrical skeleton, with pixels at its heart and calorimetres in its entrails, completed by an out skin of muon chambers and immersed in a powerful magnetic field. The ATLAS collaboration involves 38 countries, 177 institutions, and 3,000 members (1,000 phd students).

Detectors like ATLAS were created to see non visible protons and neutrons, which are invisible even under a microscope. The ATLAS detector is 93 metres underground, 46 meters in length, 25 metres diametre, and weighs 7000 tonnes – equivalent to weight of the Eiffel Tower. In its search for new particles, ATLAS measures time, charge, energy and position and can take 40 million photos per second.

In the ATLAS control room, physicists monitor every detail of the detector, continuously verifying the correct functioning of the sub-detectors, tweaking controls and carrying out exhaustive checks to ensure the information is rich and uninterrupted.

We ended the CERN tour at the Universe of Particles exhibit, where we can see displays on the first circular accelerator, a cross-section of an LHC magnet, crystal detectors, tile calorimetre, silicon pixel detectors, the first www server, how CERN traps antimatter, and the Lagrangian formula which is the standard model of particle physics.

All in all, a really fun and illuminating day. Because science! So glad I got to go on the CERN tour. Full disclosure: I’m not a physicist, I never studied high school physics (biology for me!), and tried my best to capture everything the tour guide was saying and distilling into layman’s terms. I fact-checked as best as I can afterwards to avoid inaccuracies. Hopefully there isn’t anything significant in this post.

Oh and if you do want to see the LHC accelerator in person, our tour guide said that everything will be shut down (beam, electricity, vacuum) in July 2018 for upgrades, so plan for a visit during that time.