First Direct-Detection Constraints on eV-Scale Hidden-Photon Dark Matter
  with DAMIC at SNOLAB
  We present direct detection constraints on the absorption of hidden-photon
dark matter with particle masses in the range 1.2-30 eV$c^{-2}$ with the DAMIC
experiment at SNOLAB. Under the assumption that the local dark matter is
entirely constituted of hidden photons, the sensitivity to the kinetic mixing
parameter $\kappa$ is competitive with constraints from solar emission,
reaching a minimum value of 2.2$\times$$10^{-14}$ at 17 eV$c^{-2}$. These
results are the most stringent direct detection constraints on hidden-photon
dark matter in the galactic halo with masses 3-12 eV$c^{-2}$ and the first
demonstration of direct experimental sensitivity to ionization signals $<$12 eV
from dark matter interactions.
