The angular power spectrum of the diffuse gamma-ray background as a
  probe of Galactic dark matter substructure
  Dark matter annihilation in Galactic substructure produces diffuse gamma-ray
emission of remarkably constant intensity across the sky, and in general this
signal dominates over the smooth halo signal at angles greater than a few tens
of degrees from the Galactic Center. The large-scale isotropy of the emission
from substructure suggests that it may be difficult to extract this Galactic
dark matter signal from the extragalactic gamma-ray background. I show that
dark matter substructure induces characteristic small-scale anisotropies in the
diffuse emission which may provide a robust means of distinguishing this
component. I discuss predictions for the angular power spectrum of the diffuse
emission from various extragalactic source classes as well as from Galactic
dark matter, and show that the energy dependence of the angular power spectrum
of the total measured emission could be used to confidently identify a
gamma-ray signal from Galactic dark matter.
