General calculation of the cross section for dark matter annihilations into two photons

Abstract

Assuming that the underlying model satisfies some general requirements such as renormalizability and CP conservation, we calculate the non-relativistic one-loop cross section for any self-conjugate dark matter particle annihilating into two photons. We accomplish this by carefully classifying all possible one-loop diagrams and, from them, reading off the dark matter interactions with the particles running in the loop. Our approach is general and leads to the same results found in the literature for popular dark matter candidates such as the neutralinos of the MSSM, minimal dark matter, inert Higgs and Kaluza-Klein dark matter.

MadDM v.3.0: A comprehensive tool for dark matter studies

“…The ability to automatically compute loop induced processes would be a great addition to MadDM, as it will allow the user to easy evaluate dark matter annihilation into a pair of photons or γZ or γh (the so-called smoking gun signatures for dark matter), for which the Fermi-LAT satellite is setting strong exclusion bounds [30]. At the moment such loop induced processes need to be evaluated analytically within the specific dark matter model, while there are attempts to analytically provide systematic calculations valid for the most popular dark matter candidates [39]. A fully automatised numerical procedure for any dark matter model is yet a missing block within the dark matter tools world.…”

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