First direct detection constraints on Planck-scale mass dark matter with multiple-scatter signatures using the DEAP-3600 detector

Abstract

Dark matter particles with Planck-scale mass ($\simeq 10^{19}\text{GeV}/c^2$) arise in well-motivated theories and could be produced by several cosmological mechanisms. Using a blind analysis of data collected over a 813 d live time with DEAP-3600, a 3.3 t single-phase liquid argon-based dark matter experiment at SNOLAB, a search for supermassive dark matter was performed, looking for multiple-scatter signals. No candidate signal events were observed, leading to the first direct detection constraints on Planck-scale mass dark matter. Leading limits constrain dark matter masses between $8.3\times 10^6$ and $1.2\times 10^{19}\text{GeV}/c^2$, and cross sections for scattering on ${}^{40}$Ar between $1.0\times 10^{-23}$ and $2.4\times 10^{-18}{\text{cm}}^2$. These are used to constrain two composite dark matter models.