The heatwave affecting many parts of Europe has been often in the news this summer, but we’ve also had plenty of “hot news” at CERN, in particular regarding the LHC and the experiments.
There’s been great excitement everywhere about the restart of the LHC. However, we should not forget just how much work was done during the long shutdown, and that in many ways it’s like starting up a new machine, with all the surprises that can bring. This year, the LHC has already run at the record-breaking collision energy of 13 TeV and now we’re seeing the careful, step-by-step procedure to increase the beam intensity. The aim, as it always was, is to have the collider up to its full performance by the end of the year, so that we can then embark on three years full of physics.
Nevertheless, the LHC experiments already have 100 times more data than they did at around the same time after the machine first started up at a collision energy of 7 TeV in 2010. This has allowed the experiments to renew their acquaintance with many “old friends” among the fundamental particles and processes of the Standard Model. It’s also already provided sufficient data for the first publication to come out of Run 2.
This was big news at the first of the year’s major international particle-physics conferences, the 2015 European Physical Society Conference on High Energy Physics(EPS-HEP2015), which took place recently in Vienna. Status reports on the LHC, ATLAS and CMS all figured in the main plenary sessions – and were very positively received. They included the first results at 13 TeV, with spectacular events that show the power of the energy increase. It’s clear from the conference that all eyes are on Run 2; not only particle physicists, but the physics community at large is eagerly awaiting the more significant amount of data that is to come. In the meantime, the final harvest from Run 1 continues, and can still provide exciting results, as LHCb’s discovery of a new class of particles, the pentaquarks, has amply demonstrated.
The conference also revealed a clear trend towards further exploiting the synergies between particle physics and cosmology. The two disciplines investigate two fundamental scalar fields, which appear similar and may even be connected. These are the field associated with the Brout–Englert–Higgs mechanism in particle physics, and one that is linked to a period of extremely rapid expansion, or “inflation”, in the very early Universe.
Back at CERN, the latest news concerns more than the LHC. I am pleased to announce that as from today Pakistan is an Associate Member State of CERN. Official notification that Pakistan has ratified the Association Agreement arrived through diplomatic channels this morning. I am certain that you will join me in welcoming Pakistan as an Associate Member State.