Annihilating dark matter or noise?: A statistical examination of the Fermi GeV excess around the Galactic Centre

Abstract

Excess Fermi GeV emission around the Galactic Centre has been interpreted as a possible signature of annihilating dark matter. Here we analyse three aspects of this claim: its spectral cutoff, the correlation between the spectral shape of the purported signal and known noise components, and its brightness profile. Experimentally, the correlations that exist between the GeV excess and known sources of noise make it difficult to conclude that a dark matter signal claim can be made without independent direct detection confirmation. As a possible way forward, we introduce three criteria that could potentially help to validate a dark matter annihilation signal in gamma rays.