Gamma-ray constraints on dark matter annihilation into charged particles
Nicole F Bell, Thomas D Jacques
PHYSICAL REVIEW D | AMER PHYSICAL SOC | Published : 2009
Dark matter annihilation into charged particles is necessarily accompanied by gamma rays, produced via radiative corrections. Internal bremsstrahlung from the final state particles can produce hard gamma rays up to the dark matter mass, with an approximately model-independent spectrum. Focusing on annihilation into electrons, we compute robust upper bounds on the dark matter self-annihilation cross section σAv e+e- using gamma-ray data from the Milky Way spanning a wide range of energies ∼10- 3-104GeV. We also compute corresponding bounds for the other charged leptons. We make conservative assumptions about the astrophysical inputs, and demonstrate how our derived bounds would be strengthene..View full abstract
We thank Gianfranco Bertone, Greg Mack, Stefano Profumo and Hasan Yuksel for helpful discussions, and John Beacom for detailed comments on the manuscript. N. F. B. was supported by a University of Melbourne Early Career Research Grant, and T. D. J. by the Commonwealth of Australia.