Gamma Rays from Neutralino Annihilation

Abstract

We calculate the flux of cosmic gamma rays expected {}from the annihilation of neutralinos in the Galactic halo. Our calculation of the annihilation cross section to two photons improves the existing calculations by inclusion of exact one-loop diagrams for the amplitudes involving Higgs boson and chargino states as well as those involving fermion and sfermion states. A survey of supersymmetric parameter space shows that numerous models would be observable at the $3\sigma$ level with an air Cerenkov telescope with an exposure of $10^4{\text{meter}}^2\text{yr}$.

Comments: 12 pages, self-unpacking uuencoded PostScript