Production of the DarkSide-20k photo-detectors

DarkSide-20k is a 50 t dual phase liquid argon time projection chamber currently under construction in Hall-C of LNGS. DarkSide-20k is projected to lead the search for WIMP like dark matter, probing down to WIMP-nucleon cross sections of 10−48 cm2 for a WIMP mass of 0.1 TeV. In order to achieve this goal DarkSide-20k employs novel techniques and technologies including: the use of underground argon depleted in the radioisotope 39Ar; a neutron veto integrated into the TPC mechanical structure; large-area cryogenic SiPM array photodetectors. These bespoke SiPMs, assembled into photodetector modules, instrument both the veto and TPC detectors. The design and ongoing production of these photodetector modules will be reported.