Mr Christopher Eckner (University of Nova Gorica)
A new measurement of a spatially extended gamma-ray signal from the center of M31 recently reported that the emission broadly resembles the Galactic center excess (GCE) of the Milky Way (MW). In this contribution, we discuss the possibilities that the signal originates from a population of millisecond pulsars (MSPs), or alternatively the annihilation/decay of dark matter (DM) particles. An astrophysical interpretation in terms of MSPs appears viable, even after considering higher order corrections and a broad variety of uncertainties. Guided by this result, we present an analysis to derive upper limits on the annihilation cross section of weakly interacting massive particles (WIMPs) in a mass range from 1 GeV to 10 TeV, taking into account different DM density profiles and including the effect of substructure and adiabatic contraction. Furthermore, we extend the dark matter mass range of the upper (lower) limits on the DM annihilation cross section (decay lifetime) to 100 TeV in various channels by considering the results found by the HAWC collaboration.