Assembly and qualification of the Barrel Precision Timing detector for the High Luminosity upgrade of CMS at CERN

The LHC will begin its Long Shutdown 3 (LS3) in 2026 to upgrade the accelerator for CERN's HL-LHC (High Luminosity Large Hadron Collider) era. This project focuses on precision timing measurement at the Compact Muon Solenoid (CMS) experiment. This will be achieved by working on the assembly of the barrel timing layer (BTL) which is one of the two components of the CMS minimum ionizing particle Timing Detector (MTD). This will be the first detector at collider experiments dedicated to precision timing with a resolution of 30-60 picoseconds. Construction of the BTL consists of assembling sensor modules (SMs) and detector modules (DMs). Rigorous quality assurance and control tests of SMs and DMs are performed to ensure optimal performance. The BTL is segmented into 72 trays where each tray contains 6 readout units (RU). Each RU contains 12 DMs, and a DM includes 2 SMs mounted on a front-end electronic card. This project involves activities in the assembly procedure, from building and testing modules, to constructing trays.