About CERN

by Paris Sphicas

If you were to visit www.cern.ch, and click on “About CERN” you would find the following text. It is written so well that there would be no point in re-expressing the same idea. So here it is:

The CERN logo.

“Founded in 1954, the CERN laboratory sits astride the Franco-Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 21 member states. The name CERN is derived from the acronym for the French “Conseil Européen pour la Recherche Nucléaire”, or European Council for Nuclear Research, a provisional body founded in 1952 with the mandate of establishing a world-class fundamental physics research organization in Europe. At that time, pure physics research concentrated on understanding the inside of the atom, hence the word “nuclear”. 

Today, our understanding of matter goes much deeper than the nucleus, and CERN’s main area of research is particle physics – the study of the fundamental constituents of matter and the forces acting between them. Because of this, the laboratory operated by CERN is often referred to as the European Laboratory for Particle Physics.”

A lot of water has flown under the bridge since the 50s. By now, CERN is the world’s premier particle physics laboratory, and the celebrated setting of the Large Hadron Collider, the LHC, which includes four experiments. The two large, “general-purpose” experiments, ATLAS and CMS, aim to study all characteristics of the proton-proton collisions offered by CERN.

The LHC and its four experiments: ATLAS, CMS, ALICE, and LHCb.

The best-known discoveries of experiments at CERN are (a) neutral currents in the 70s by Gargamelle (b) the W and Z bosons of electroweak theory in the 80s, by UA1 and UA2 and (c) the Higgs boson, the last element of the Standard Model of Particle Physics, in 2012, by ATLAS and CMS. Over the past thirty years, CERN experiments have made seminal contributions in establishing the “Standard Model” into the “Standard Theory” of particle physics. All in parallel with creating technology, amongst which the invention of the World-Wide Web, the ubiquitous www, in the 90s.

Nowadays, the LHC represents the “energy frontier” in particle physics – the place where, traditionally, new physics has been showing up throughout the past hundred years. The LHC experiments are trying to answer “next-gen” questions such as “what stabilizes the mass of the Higgs boson”?

Incredibly, if one goes through the mathematics of a particle that would have all the properties of the Higgs boson (and thus give mass to all the other particles) one realizes that the mass of this particle should be infinite – or whatever comes close to infinity. Yet, infinite it is not, for it has been discovered at a very finite mass of ~130 protons.

Is there some new mechanism in nature that cancels this infinity? Or, perhaps this new entity, the Higgs boson, a particle like no other, for it has the characteristics of the vacuum, can “see” and “feel” into hidden worlds like dark matter? Could it be a portal into this mysterious form of matter that keeps galaxies from flying apart, and, most importantly, seems to be necessary for the very formation of the galaxies in our universe?

The hunt goes on. CMS and ATLAS just started operating at the new energy frontier of 13 TeV, looking for the unknown. This “look” is complicated: there are billions of events to sift through, hundreds of characteristics to look for. And many Standard Model processes that are produced much more copiously than the new posited physics. In this battle, for a battle it is, the experiments are trying to employ the latest greatest tools. Thus the involvement in the AMVA4NewPhysics ITN, which is funded by the European Commission’s Marie Curie Program.

CERN is participating in AMVA4NewPhysics with three components – an unprecedented feat: one group is working on the CMS experiment and is carrying out searches for new physics, including “Supersymmetry” and “Dark Matter”. A second group is working on the ATLAS experiment and is studying methods of increasing the precision of measurements of the top quark. A third group is working on theoretical particle physics and in particular extensions of the Standard Model.

Each one of these groups will be hiring an “ESR” (EC-ese for “Early Stage Researcher”, meaning “someone with a Master’s degree, and no more than four years away from the award of this degree”) to work on these hot topics.

May the fun begin. Well, “continue”, is actually a more appropriate term.