Can Astrophysical Gamma Ray Sources Mimic Dark Matter Annihilation in Galactic Satellites?

Abstract

The nature of the cosmic dark matter is unknown. The most compelling hypothesis is that dark matter consists of weakly interacting massive particles (WIMPs) in the 100 GeV mass range. Such particles would annihilate in the galactic halo, producing high-energy gamma rays which might be detectable in gamma ray telescopes such as the GLAST satellite. We investigate the ability of GLAST to distinguish between WIMP annihilation sources and astrophysical sources. Focusing on the galactic satellite halos predicted by the cold dark matter model, we find that the WIMP gamma-ray spectrum is nearly unique; separation of the brightest WIMP sources from known source classes can be done in a convincing way by including spectral and spatial information. Candidate WIMP sources can be further studied with Imaging Atmospheric Cerenkov Telescopes. Finally, Large Hadron Collider data might have a crucial impact on the study of galactic dark matter.