Light Collection and Simulation for nEXO*

nEXO is a next-generation 5-tonne liquid xenon time projection chamber that will search for neutrinoless double beta decay (0νββ) of Xe-136. The experiment has a projected half-life sensitivity of 1.35 x 10²⁸ years over 10 years of livetime, which sets a design goal of 0.8% energy resolution (σ_E/E) at the decay Q-value of 2.458 MeV. Achieving this goal requires optimizing the collection of scintillation photons from energy deposits in liquid xenon. To this end, nEXO will employ approximately 46,000 silicon photomultipliers (SiPMs) positioned around the detector’s barrel to detect the vacuum ultra-violet, 175 nm scintillation light of liquid xenon. In this talk I will describe candidate SiPMs for nEXO and current efforts to simulate the light detection performance of the full detector and leverage the experiment’s high pixelation for photoimaging of events.