1206.7056 (Wilfried Buchmuller et al.)

Decaying vs Annihilating Dark Matter in Light of a Tentative Gamma-Ray Line    [PDF]

Wilfried Buchmuller, Mathias Garny

Recently reported tentative evidence for a gamma-ray line in the Fermi-LAT data is of great potential interest for identifying the nature of dark matter. We compare the implications for decaying and annihilating dark matter taking the constraints from continuum gamma-rays, antiproton flux and morphology of the excess into account. We find that higgsino and wino dark matter are excluded, also for nonthermal production. Generically, the continuum gamma-ray flux severely constrains annihilating dark matter. Consistency of decaying dark matter with the spatial distribution of the Fermi-LAT excess would require an enhancement of the dark matter density near the Galactic center.

View original: http://arxiv.org/abs/1206.7056