Search for dark matter with a 231-day exposure of liquid argon using
  DEAP-3600 at SNOLAB
  DEAP-3600 is a single-phase liquid argon (LAr) direct-detection dark matter
experiment, operating 2 km underground at SNOLAB (Sudbury, Canada). The
detector consists of 3279 kg of LAr contained in a spherical acrylic vessel.
This paper reports on the analysis of a 758 tonne\cdot day exposure taken over
a period of 231 live-days during the first year of operation. No candidate
signal events are observed in the WIMP-search region of interest, which results
in the leading limit on the WIMP-nucleon spin-independent cross section on a
LAr target of $3.9\times10^{-45}$ cm$^{2}$ ($1.5\times10^{-44}$ cm$^{2}$) for a
100 GeV/c$^{2}$ (1 TeV/c$^{2}$) WIMP mass at 90\% C. L. In addition to a
detailed background model, this analysis demonstrates the best pulse-shape
discrimination in LAr at threshold, employs a Bayesian photoelectron-counting
technique to improve the energy resolution and discrimination efficiency, and
utilizes two position reconstruction algorithms based on PMT charge and photon
arrival times.
