Rate for annihilation of galactic dark matter into two photons

Publisher Website
Google Scholar
Abstract
We perform a calculation of the cross section for neutralino-neutralino annihilation into two photons and apply it to dark matter in the galactic halo to find the counting rate in a large γ-ray detector such as EGRET or ASTROGAM. Combining constraints from particle accelerators with the requirement that the neutralinos make up the dark matter we find that rates over a few dozen events per year are unlikely. We list the assumptions that go into our conclusions and suggest other particle dark-matter candidates which could give larger and perhaps observable signals.