Are We Looking at Neutrino Absorption Spectra at IceCube?

TL;DR

This paper explores the possibility that ultrahigh energy neutrino spectra observed at IceCube are affected by absorption in ultralight dark matter halos, proposing a new interaction mechanism that could influence astrophysical models.

Contribution

It introduces a novel absorption mechanism via a light Z'-mediated interaction, explaining spectral features and impacting models predicting high-energy neutrino fluxes.

Findings

Features of the neutrino spectrum can be explained by absorption in dark matter halos.

A new Z'-mediated interaction mechanism causes energy-specific neutrino absorption.

This mechanism can modify predictions of astrophysical neutrino flux models.

Abstract

The observed spectrum of ultrahigh energy neutrinos at IceCube might be indicative of absorption of such neutrinos in ultralight dark matter halos. We point out that various features of this spectrum can be explained by such absorptions. For a light $Z^\prime$-mediated $t$-channel interaction between dark matter and neutrinos, we propose a novel mechanism of absorption of these neutrinos at particular energies. This can save the models of AGN predicting large neutrino flux at energies more than a PeV.