A Spin-Dependent Interpretation for Possible Signals of Light Dark
  Matter
  Signals broadly compatible with light (7-10 GeV) dark matter have been
reported in three direct detection experiments: CoGeNT, DAMA/LIBRA, and CDMS-II
silicon. These possible signals have been interpreted in the context of
spin-independent interactions between the target nuclei and dark matter,
although there is tension with null results, particularly from xenon-based
experiments. In this paper, we demonstrate that the CoGeNT and CDMS-II silicon
results are also compatible assuming a spin-dependent neutron interaction,
though this is in tension with xenon-based experiments and PICASSO. The tension
with the null results from XENON100 and XENON10 is approximately the same as
for the spin-independent coupling. All three experimental signals can be made
compatible through a combination of spin-dependent interactions with both the
proton and neutron, although such a scenario increases the conflict with the
null results of other experiments.
