IceCube PeV Neutrinos and Leptophilic Dark Matter

TL;DR

This paper proposes a model explaining IceCube's high-energy neutrino events through a combination of astrophysical sources and leptophilic dark matter decay, predicting a PeV energy cutoff and anisotropy towards the Galactic Center.

Contribution

It introduces a leptophilic three-body decay model for heavy dark matter explaining PeV neutrinos, improving fit to IceCube data over previous models.

Findings

Better agreement with IceCube data using a 100 TeV cutoff for astrophysical sources.

Predicts a sharp PeV cutoff in neutrino flux due to dark matter decay.

Forecasts anisotropy towards Galactic Center as a testable signature.

Abstract

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.