The angular power spectrum of the diffuse gamma-ray emission as measured by the Fermi Large Area Telescope and constraints on its Dark Matter interpretation

Understand

The isotropic gamma-ray background arises from the contribution of unresolved sources, including members of confirmed source classes and proposed gamma-ray emitters such as the radiation induced by dark matter annihilation and decay.

• Clues about the properties of the contributing sources are imprinted in the anisotropy characteristics of the gamma-ray background.
• We use 81 months of Pass 7 Reprocessed data from the Fermi Large Area Telescope to perform a measurement of the anisotropy angular power spectrum of the gamma-ray background.
• We analyze energies between 0.5 and 500 GeV, extending the range considered in the previous measurement based on 22 months of data.