Séminaire: LHCb Tracking System: Past, Present and Future

par Dr Mark TOBIN (EPFL (Lausanne))

mardi 16 févr. 2016, 14:30 → 15:30 Europe/Paris

Amphi Recherche (Dept.Phys.)

The LHCb experiment is dedicated to the study of heavy flavour physics at the Large Hadron Collider (LHC). The primary goal of the experiment is to search for indirect evidence of new physics via measurements of CP violation and rare decays of beauty and charm hadrons. The LHCb detector is a single-arm forward spectrometer and includes a high-precision tracking system consisting of a silicon-strip vertex detector surrounding the proton-proton interaction region, a large-area silicon-strip detector located upstream of a dipole magnet, and three stations of silicon-strip detectors and straw drift tubes placed downstream of the magnet. The LHCb detector will be upgraded during 2019/20 in order to collect data from proton-proton collisions at the LHC at higher instantaneous luminosities and to read out the data at 40MHz using a trigger-less read-out system. All front-end electronics will be replaced and several sub-detectors must be redesigned to cope with the higher occupancy. The current tracking detectors downstream of the LHCb dipole magnet will be replaced by the Scintillating Fibre (SciFi) Tracker. The SciFi Tracker will be constructed using 2.5m long scintillating fibres and read out by Silicon Photomultipliers (SiPM) located outside the acceptance. The performance and operation of the silicon tracking detectors during LHC Run 1 will be presented together with latest measurements of the observed radiation damage. The focus will then shift to the various challenges involved in the design and construction of the SciFi Tracker: the radiation hardness of the fibres and the SiPMs; the mechanical precision required while building large active detector components; and the cooling required to mitigate the effects of radiation damage.