Distinguishing among dark matter annihilation channels with neutrino telescopes

TL;DR

This paper explores how neutrino telescopes can differentiate dark matter annihilation channels by analyzing neutrino spectra and flavor signatures, even with experimental uncertainties, especially for dark matter masses above 300 GeV.

Contribution

It introduces methods to distinguish neutrino final states and their flavors from muon spectra and $ u_ au$ regeneration effects, advancing dark matter detection techniques.

Findings

Muon spectra can discriminate neutrino final states.

$ u_ au$ regeneration helps identify neutrino flavors.

Multi-year IceCube/DeepCore data can distinguish primary neutrinos.

Abstract

We investigate the prospects for distinguishing dark matter annihilation channels using the neutrino flux from gravitationally captured dark matter particles annihilating inside the sun. We show that, even with experimental error in energy reconstruction taken into account, the spectrum of contained muon tracks may be used to discriminate neutrino final states from the gauge boson/charged lepton final states and to determine their corresponding branching ratios. We also discuss the effect of $\nu_\tau$ regeneration inside the sun as a novel method to distinguish the flavor of final state neutrinos. This effect as evidenced in the muon spectrum becomes important for dark matter masses above 300 GeV. Distinguishing primary neutrinos and their flavor may be achieved using multi-year data from a detector with the same capability and effective volume as the IceCube/DeepCore array.