Speaker
Description
The DEAP-3600 Collaboration recently released results describing an ultra-low background search
for non-baryonic dark matter at SNOLAB, reaching a sensitivity of $3.9\times 10^{-45}\;\mbox{cm}^2$
for a 100 GeV/c$^2$ WIMP mass. A background model was constructed, tuned on the sidebands,
used to inform data-selection cuts, and used to predict rates in the region of interest for
WIMP interactions ($0.62^{+0.31}_{-0.28}$ events in the 231-day exposure). The model includes leakage of
electromagnetic events from pulse-shape discrimination; Cherenkov events; surface events with
nuclear recoils or straggling alphas entering the argon; fast neutrons; and alpha decays in
which only a fraction of the light enters the detector (so-called "neck events"). The background
model will be discussed along with potential future improvements. Ideas of how the DEAP-3600
results informs larger liquid argon detectors will be presented.
