Heavy right-handed neutrino dark matter and PeV neutrinos at IceCube

TL;DR

This paper proposes a non-supersymmetric model where heavy right-handed neutrinos serve as long-lived dark matter, potentially explaining IceCube's PeV neutrino events through decay processes.

Contribution

It introduces a novel electroweak gauge model with resonant annihilation to achieve correct relic density and links dark matter decay to observed high-energy neutrinos.

Findings

Dark matter decay can produce PeV neutrinos consistent with IceCube data

Resonant s-channel annihilation relaxes unitarity bounds on dark matter mass

Model predicts observable flavor signatures in future neutrino observations

Abstract

We discuss a simple non-supersymmetric model based on the electroweak gauge group $SU(2)_L\times SU(2)^\prime\times U(1)_{B-L}$ where the lightest of the right-handed neutrinos, which are part of the leptonic doublet of $SU(2)^\prime$, play the role of a long-lived unstable dark matter with mass in the multi-PeV range. We use a resonant $s$-channel annihilation to obtain the correct thermal relic density and relax the unitarity bound on dark matter mass. In this model, there exists a 3-body dark matter decay mode producing tau leptons and neutrinos, which could be the source for the PeV cascade events observed in the IceCube experiment. The model can be tested with more precise flavor information of the highest-energy neutrino events in future data.