Triple-GEM detectors for the upgrade of CMS

The discovery of the Higgs boson by the ATLAS and CMS collaborations in 2012 has been the start of a major work program of the Large Hadron Collider (LHC) to measure this particle’s properties with the highest possible precision for testing the validity of the Standard Model and to search for further new physics at the energy frontier. Top priority has been given to the exploitation of the full potential of the LHC, including the high-luminosity upgrade of the machine and detectors with a view to collecting ten times more data than in the initial design, by around 2030.

The LHC will be upgraded in several phases, after the long shutdown 2 (LS2 in 2019-2020) the accelerator luminosity will reach 2 − 3 × 1034 cm−2 s−1 and after LS3 (2024-2026) up to 5 × 1034 cm−2 s−1. This increase of luminosity will result in more overlapping proton-proton collisions (pile-up) and much higher background levels. To enable CMS to continue high quality data-taking several upgrades are currently ongoing. Among the upgrades, the installation of new muon stations based on Gas Electron Multiplier (GEM) technology is one of CMS main priorities during LS2.

In this seminar I will present different steps of the CMS GEM Upgrade, explain the GEM technology and give an overview of almost 10 years of R&D necessary to fulfil the CMS requirements. Thereafter I will show the organization of the mass-production of the final detectors having allowed us to produce in time 160 detectors in 5 sites all over the world; give an overview of the ongoing installation and commissioning together with a discussion of future developments in the field.

Speaker: Jeremie Merlin (INFN Bari)