IceCube Search for Dark Matter Annihilation in nearby Galaxies and Galaxy Clusters

TL;DR

This paper reports a search for dark matter annihilation signals in nearby galaxies and clusters using IceCube neutrino data, setting upper limits on annihilation cross sections for various particle masses and channels.

Contribution

First search for self-annihilating dark matter in nearby galaxies and clusters using IceCube neutrino data, providing new constraints on dark matter properties.

Findings

Set upper limits on annihilation cross sections for dark matter particles between 300 GeV and 100 TeV.

Challenged the WIMP interpretation of the GeV positron excess assuming subhalo effects.

Provided constraints for multiple annihilation channels including b bbar, W+W-, τ+τ-, μ+μ-, and ν ν bar.

Abstract

We present the results of a first search for self-annihilating dark matter in nearby galaxies and galaxy clusters using a sample of high-energy neutrinos acquired in 339.8 days of live time during 2009/10 with the IceCube neutrino observatory in its 59-string configuration. The targets of interest include the Virgo and Coma galaxy clusters, the Andromeda galaxy, and several dwarf galaxies. We obtain upper limits on the cross section as a function of the weakly interacting massive particle mass between 300 GeV and 100 TeV for the annihilation into b bbar, W+W-, \tau+\tau-, \mu+\mu-, and \nu \nu bar. A limit derived for the Virgo cluster, when assuming a large effect from subhalos, challenges the weak interacting massive particle interpretation of a recently observed GeV positron excess in cosmic rays.