Relative Measurement and Extrapolation of the Scintillation Quenching Factor of $\hat{I}\pm$-Particles in Liquid Argon using DEAP-3600 Data

Abstract

The knowledge of scintillation quenching of $\hat{I}\pm$-particles plays a paramount role in understanding $\hat{I}\pm$-induced backgrounds and improving the sensitivity of liquid argon-based direct detection of dark matter experiments. We performed a relative measurement of scintillation quenching in the MeV energy region using radioactive isotopes (${}^{222}$Rn, ${}^{218}$Po and ${}^{214}$Po isotopes) present in trace amounts in the DEAP-3600 detector and quantified the uncertainty of extrapolating the quenching factor to the low-energy region.

9 pages, 6 figures