The upgrade of the Muon System of the CMS experiment

Abstract

The CMS muon system is based on three types of gaseous detectors, RPC, CSC and DT. While operating very well in the present conditions, upgrades are foreseen for each of the subsystems, necessary to cope with the increased pile-up, coming along with higher rates and radiation, during the upcoming periods of data taking.Moreover, an important issue will be to make the system able to perform its delicate task of muon triggering and tracking also in the High Luminosity phase of LHC, foreseen to start after Long Shutdown 3 in 2023 and to last for about 10 years.Studies devoted to asses the system perfomance stability for the future will be presented. In addition, the stategy -which is being developed -to complement the existing system with new detectors, based on GEM or improved RPC technologies, will be shown. ABSTRACT:The CMS Muon System is based on three types of gaseous detectors, Resistive Plate Chambers, Cathods Strip Chambers and Drift Tubes. While operating very well in the present conditions, upgrades are foreseen for each of the subsystems, necessary to cope with the increased pile-up, coming along with higher rates and radiation, during the upcoming periods of data taking. Moreover, an important issue will be to make the system able to perform its delicate task of muon triggering and tracking also in the High Luminosity phase of LHC, foreseen to start after Long Shutdown 3 in 2023 and to last for about 10 years. Studies devoted to asses the system perfomance stability for the future will be presented. In addition, the strategy -which is being developed -to complement the existing system with new detectors, based on Gas Electron Multipliers or improved RPC technologies, will be shown.

RE3/1 & RE4/1 RPC chambers integration in the inner region of the forward muon spectrometer in the CMS experiment

“…Before this upgrade, eight RPC layers in total were installed in the four existing endcap disks covering up to the value of pseudorapidity |η| < 1.9. At the moment the very forward region still remains incomplete after first Long Shutdown (LS1) and could be instrumented up to |η| = 2.4 during second Long Shutdown (LS2) (for GEM project) and annual Year-End Technical Stops 2022 & 2023 (for iRPC project) (figure 1) [1]. The presence of an inner layer in the endcap region equipped with new improved RPC stations, called RE3/1 & RE4/1, will increase the overall robustness of the CMS muon spectrometer.…”