A blueprint for detecting supersymmetric dark matter in the Galactic halo

Abstract

Dark matter is the dominant form of matter in the universe, but its nature is unknown. It is plausibly an elementary particle, perhaps the lightest supersymmetric partner of known particle species. In this case, annihilation of dark matter in the halo of the Milky Way should produce gamma-rays at a level which may soon be observable. Previous work has argued that the annihilation signal will be dominated by emission from very small clumps (perhaps smaller even than the Earth) which would be most easily detected where they cluster together in the dark matter halos of dwarf satellite galaxies. Here we show, using the largest ever simulation of the formation of a galactic halo, that such small-scale structure will, in fact, have a negligible impact on dark matter detectability. Rather, the dominant and likely most easily detectable signal will be produced by diffuse dark matter in the main halo of the Milky Way. If the main halo is strongly detected, then small dark matter clumps should also be visible, but may well contain no stars, thereby confirming a key prediction of the Cold Dark Matter (CDM) model.

to appear in Nature, 23 pages, 8 figures, includes Supplementary Information

References in corpus (3)

• Precise constraints on the dark matter content of Milky Way dwarf galaxies for gamma-ray experiments
• Pre-launch estimates for GLAST sensitivity to Dark Matter annihilation signals
• Extracting the Gamma Ray Signal from Dark Matter Annihilation in the Galactic Center Region

Cited by in corpus (7)

• Phase-space structure in the local dark matter distribution and its signature in direct detection experiments
• The Gamma-Ray-Flux Probability Distribution Function from Galactic Halo Substructure
• Substructure Boosts to Dark Matter Annihilation from Sommerfeld Enhancement
• Star Clusters Around Recoiled Black Holes in the Milky Way Halo
• The impact of baryons on dark matter haloes
• Dark Matter Caustics
• A luminosity constraint on the origin of unidentified high energy sources