Testing the Dark Matter Scenario for PeV Neutrinos Observed in IceCube

TL;DR

This paper explores the hypothesis that decaying heavy dark matter could explain the PeV neutrinos detected by IceCube, analyzing constraints from gamma-ray data and future observational prospects.

Contribution

It evaluates the consistency of dark matter decay models with multimessenger data and proposes future observational tests to confirm or refute this scenario.

Findings

Models are marginally consistent with gamma-ray background data.

Future gamma-ray observations can test the models.

Next-generation neutrino telescopes can potentially rule out or support the dark matter hypothesis.

Abstract

Late time decay of very heavy dark matter is considered as one of the possible explanations for diffuse PeV neutrinos observed in IceCube. We consider implications of multimessenger constraints, and show that proposed models are marginally consistent with the diffuse gamma-ray background data. Critical tests are possible by a detailed analysis and identification of the sub-TeV isotropic diffuse gamma-ray data observed by Fermi and future observations of sub-PeV gamma rays by observatories like HAWC or Tibet AS+MD. In addition, with several-year observations by next-generation telescopes such as IceCube-Gen2, muon neutrino searches for nearby dark matter halos such as the Virgo cluster should allow us to rule out or support the dark matter models, independently of gamma-ray and anisotropy tests.