The LHC (Large Hadron Collider), the largest particle accelerator in the world, has resumed work in preparation for the new work program, code-named Run 3, which is scheduled to start in July. The initial operations are the ones necessary to test the equipment after more than three years of update work. On April 22, the first proton beams were injected in opposite directions into the 27-kilometer the LHC ring. If all goes as planned, Run 3 will begin in July pending the completion of other works that will lead to the enhanced version called High Luminosity the LHC (HiLumi LHC or simply HL-LHC).
The update made during the period called long shutdown 2 made it possible to carry out a large amount of work on the LHC’s equipment and the various experiments present in the different collision points of the particle beams. In some cases, it was maintenance, in many others, there was an upgrade of the equipment. The experiments are marked by detectors, key elements in the work of the LHC because they measure the particles generated by collisions. Run 3 includes two new experiments: FASER (Forward Search Experiment) and SND@LHC (Scattering and Neutrino Detector at the LHC). These are two experiments designed to investigate various aspects of the physical theory known as the Standard Model with the possibility of going beyond it.
The work was long and complex but necessary to ensure at the same time an increase in the collision energy and above all in the amount of data that will be collected. The improvements in data collection will be different in the various experiments and overall will allow more data to be collected in Run 3 than in the two previous Runs combined.
The works of Run 3 will allow exploring limits of physics that so far it has only been possible to glimpse even with the LHC and to study in more detail particles such as the famous Higgs boson. These are tasks that will become even more important with the completion of HiLumi LHC, which should occur in 2026 for a start of scientific activity that could begin in 2028.
The first test conducted on April 22, 2022, reached relatively low energies, at 450 GeV. Over the next few days, the tests gradually increased the energies, which will eventually reach the new peak level of 13.6 TeV. These are time-consuming operations, as they must be carried out one step at a time to prevent a possible problem from causing major damage to the equipment. The goal is to reach a new level of knowledge in the field of particle physics, closely connected to our knowledge of the cosmos.
