Prospects For Detecting Dark Matter With GLAST In Light Of The WMAP Haze

TL;DR

This paper explores the potential for the GLAST satellite to detect gamma rays from dark matter annihilations in the Galactic Center, motivated by the WMAP Haze, and assesses detection prospects based on dark matter properties and halo profiles.

Contribution

It provides a detailed analysis of GLAST's ability to detect gamma rays from dark matter annihilations consistent with the WMAP Haze, considering various particle masses and annihilation channels.

Findings

GLAST can detect dark matter particles lighter than 320-750 GeV with high significance.

Broader angular studies can identify heavy WIMPs up to several TeV.

Detection is unlikely if dark matter mainly annihilates to electrons or muons.

Abstract

Observations by the WMAP experiment have identified an excess of microwave emission from the center of the Milky Way. It has previously been shown that this "WMAP Haze" could be synchrotron emission from relativistic electrons and positrons produced in the annihilations of dark matter particles. In particular, the intensity, spectrum and angular distribution of the WMAP Haze is consistent with an electroweak scale dark matter particle (such as a supersymmetric neutralino or Kaluza-Klein dark matter in models with universal extra dimensions) annihilating with a cross section on the order of sigma v~3x10^-26 cm^3/s and distributed with a cusped halo profile. No further exotic astrophysical or annihilation boost factors are required. If dark matter annihilations are in fact responsible for the observed Haze, then other annihilation products will also be produced, including gamma rays. In this article, we study the prospects for the GLAST satellite to detect gamma rays from dark matter annihilations in the Galactic Center region in this scenario. We find that by studying only the inner 0.1 degrees around the Galactic Center, GLAST will be able to detect dark matter annihilating to heavy quarks or gauge bosons over astrophysical backgrounds with 5sigma (3sigma) significance if they are lighter than approximately 320-500 GeV (500-750 GeV). If the angular window is broadened to study the dark matter halo profile's angular extension (while simultaneously reducing the astrophysical backgrounds), WIMPs as heavy as several TeV can be identified by GLAST with high significance. Only if the dark matter particles annihilate mostly to electrons or muons will GLAST be unable to identify the gamma ray spectrum associated with the WMAP Haze.