Muon Veto Design for Darkside-20k

The DarkSide-20k (DS-20k) detector will be a two-phase Liquid Argon Time Projection Chamber (LAr TPC), designed to directly detect WIMP-like dark matter at INFN Gran Sasso National Laboratory (LNGS). The TPC is housed within an outer muon veto which consists of a 650 ton atmospheric argon bath, with SiPM photosensors to collect in situ background measurements from the AAr scintillation. The stainless steel walls of the outer veto are coated with a reflector and wavelength shifter to optimize the light yield from energy deposited from cosmic ray showers. Currently, work is being done to simulate the expected detection rate and data requirements in the outer veto.