An Overview of Detector Module Assembly for the Barrel Timing Layer of the HL-LHC Upgrade for the CMS Experiment

The Barrel Timing Layer (BTL) upgrade to the Compact Muon Solenoid (CMS) experiment is a key component for the upgrade to the Large Hadron Collider (LHC) into the High Luminosity era LHC (HL-LHC) at CERN, the European Organization for Nuclear Research. The CMS detector is a general purpose detector used for purposes ranging from studying the Standard Model to searching for extra dimensions and particles that could potentially comprise dark matter. The single-layer BTL upgrade seeks to improve the timing resolution of CMS down to the range of 30-40 picoseconds for the purpose of detecting minimum ionizing particles (MIPs). A constituent unit of this MIP timing detector is a detector module: a piece of hardware which combines with electronics two sensor modules, which are themselves composed of LYSO crystals as scintillators and Silicon Photomultipliers (SiPMs) as photosensors. These detector modules serve an additional purpose of removing heat from the sensitive BTL components via a Cu housing; heat management ultimately drives the achievable time resolution of the upgrade, These detector modules are then incorporated into trays, which are the penultimate units for the BTL upgrade. The BTL assembly center at the University of Virginia (UVA) is involved in all parts of this process; however, the scope of this talk will exclusively focus on the process of assembly and quality assessment/control testing for detector modules.