Can Neutron stars constrain Dark Matter?
  We argue that observations of old neutron stars can impose constraints on
dark matter candidates even with very small elastic or inelastic cross section,
and self-annihilation cross section. We find that old neutron stars close to
the galactic center or in globular clusters can maintain a surface temperature
that could in principle be detected. Due to their compactness, neutron stars
can acrete WIMPs efficiently even if the WIMP-to-nucleon cross section obeys
the current limits from direct dark matter searches, and therefore they could
constrain a wide range of dark matter candidates.
