IceCube PeV Neutrinos and Leptophilic Dark Matter
  We analyze the scenario where the IceCube high energy neutrino events are
explained in terms of an extraterrestrial flux due to two different components:
a contribution coming from know astrophysical sources for energies up to few
hundreds TeV and a top-down contribution originated by the decay of heavy dark
matter particles with a mass of few PeV. Contrary to previous approaches, we
consider a leptophilic three-body decay that dominates at PeV energies due to
the absence of quarks in the final state. We find that the theoretical
predictions of such a scenario are in a slightly better agreement with the
IceCube data if the astrophysical component has a cut-off at about 100 TeV.
This interpretation of IceCube data can be easily tested in the near future
since the decaying dark matter scenario predicts a sharp cut-off at PeV energy
scale and the observation of an anisotropy towards Galactic Center of our
Galaxy in contrast with the isotropic astrophysical flux.
