Enhancing Dark Matter Annihilation into Neutrinos
  We perform a detailed and quasi model-independent analysis of direct
annihilation of Dark Matter into neutrinos. Considering different cases for
scalar and fermionic Dark Matter, we identify several settings in which this
annihilation is enhanced, contrary to some statements in the literature. They
key point is that several restrictions of, e.g., a supersymmetric framework do
not hold in general. The mass generation mechanism of the neutrinos plays an
important role, too. We illustrate our considerations by two examples that are
not (as usually) suppressed by the smallness of the neutrino mass, for which we
also present a numerical analysis. Our results can be easily used as guidelines
for model building.
