The LEAR Detector: Simulation and Construction of a Test Bed for Low Energy Recoils in Liquid Argon

Abstract

Direct detection is a fundamental experimental technique in the search for dark matter candidate particles. In particular, the search for Weakly Interacting Massive Particles (WIMPs) as a viable candidate for dark matter with a mass between 10 GeV ∼ 1 TeV. Cryogenic noble gases are a popular medium for WIMP detection due to their emission of scintillation light. Liquid Argon (LAr) scintillation signals arise from nuclear recoils caused by the interaction of WIMPs and argon nuclei through the weak force. The resulting scintillation light and ionized electrons can be used to reconstruct an event’s 3D position and deposition time by using a dual-phase Time Projection Chamber (TPC). The implementation of large-scale LAr TPCs is the primary focus of the DarkSide collaboration. To help facilitate this, a smaller-scale TPC is being constructed to understand low energy argon recoil (LEAR) signatures. Monte Carlo simulations were used to understand the signals of elastic neutron scattering in LEAR’s LAr TPC. Also, preparing the deposition of a conductive, transparent film of Indium Tin Oxide (ITO) onto LEAR’s fused silica anode and cathode was completed. The properties of this ITO film are similar to the results achieved in previous ITO depositions from DarkSide-50.