The Sensitivity of the IceCube Neutrino Detector to Dark Matter Annihilating in Dwarf Galaxies

TL;DR

This study evaluates IceCube's ability to detect dark matter annihilation signals in dwarf galaxies, comparing its sensitivity to gamma-ray telescopes and highlighting conditions where IceCube is most effective.

Contribution

It provides a comparative analysis of neutrino and gamma-ray observations for dark matter detection, focusing on IceCube's potential in various annihilation scenarios.

Findings

IceCube's sensitivity is comparable to gamma-ray telescopes for dark matter masses >7 TeV or <200 GeV.

IceCube outperforms gamma-ray telescopes for tau+tau- annihilation below 200 GeV.

Neutrino-antineutrino annihilation channels significantly enhance IceCube's detection prospects.

Abstract

In this paper, we compare the relative sensitivities of gamma-ray and neutrino observations to the dark matter annihilation cross section in leptophilic models such as have been designed to explain PAMELA data. We investigate whether the high energy neutrino telescope IceCube will be competitive with current and upcoming searches by gamma-ray telescopes, such as the Atmospheric Cerenkov Telescopes (ACTs) (HESS, VERITAS and MAGIC), or the Fermi Gamma Ray Space Telescope, in detecting or constraining dark matter particles annihilating in dwarf spheroidal galaxies. We find that after ten years of observation of the most promising nearby dwarfs, IceCube will have sensitivity comparable to the current sensitivity of gamma-ray telescopes only for very heavy (m_X > 7 TeV) or relatively light (m_X < 200 GeV) dark matter particles which annihilate primarily to mu+mu-. If dark matter particles annihilate primarily to tau+tau-, IceCube will have superior sensitivity only for dark matter particle masses below the 200 GeV threshold of current ACTs. If dark matter annihilations proceed directly to neutrino-antineutrino pairs a substantial fraction of the time, IceCube will be competitive with gamma-ray telescopes for a much wider range of dark matter masses.