Speaker
Description
The Andromeda galaxy (M31) is a promising target for the indirect search of dark matter (DM) due to its proximity and expected massive DM halo. It functions as test case for a Milky Way (MW) like galaxy as the isotropic emission from the MW halo itself cannot be detected with a coded mask telescope like INTEGRAL/SPI. MeV data can put strong limits on DM models from the MeV up to the TeV mass range since weakly interacting massive particles also produce a significant flux of secondary MeV photons from inverse Compton scattering and positron annihilation.
We use the spectrum obtained from observations of M31 with SPI in order to constrain different DM models. From the 511 keV emission from positron annihilation, we estimate the pair production rate in M31 to put a lower mass limit on thermal DM. We take the uncertainty of the DM distribution into account by considering different density profiles and substructure boosting.
