Probing dark matter signals in neutrino telescopes through angular power spectrum

TL;DR

This paper investigates the potential of neutrino telescopes to detect dark matter signals by analyzing the angular power spectrum of neutrino sky maps, distinguishing dark matter from astrophysical sources.

Contribution

It introduces an angular power spectrum analysis method to differentiate dark matter signals from astrophysical neutrinos and provides sensitivity forecasts for future detectors.

Findings

KM3NeT is more sensitive than IceCube-Gen2 at low energies.

After 10 years, current dark matter scenarios can be firmly tested.

Angular analysis can effectively probe dark matter contributions.

Abstract

The hypothesis of two different components in the high-energy neutrino flux observed with IceCube has been proposed to solve the tension among different data-sets and to account for an excess of neutrino events at 100 TeV. In addition to a standard astrophysical power-law component, the second component might be explained by a different class of astrophysical sources, or more intriguingly, might originate from decaying or annihilating dark matter. These two scenarios can be distinguished thanks to the different expected angular distributions of neutrino events. Neutrino signals from dark matter are indeed expected to have some correlation with the extended galactic dark matter halo. In this paper, we perform angular power spectrum analyses of simulated neutrino sky maps to investigate the two-component hypothesis with a contribution from dark matter. We provide current constraints and expected sensitivity to dark matter parameters for future neutrino telescopes such as IceCube-Gen2 and KM3NeT. The latter is found to be more sensitive than IceCube-Gen2 to look for a dark matter signal at low energies towards the galactic center. Finally, we show that after 10 years of data-taking, they will firmly probe the current best-fit scenario for decaying dark matter by exploiting the angular information only.