Radio and gamma-ray constraints on dark matter annihilation in the Galactic center

Abstract

We determine upper limits on the dark matter (DM) self-annihilation cross section for scenarios in which annihilation leads to the production of electron-positron pairs. In the Galactic center, relativistic electrons and positrons produce a radio flux via synchroton emission, and a gamma-ray flux via bremsstrahlung and inverse Compton scattering. On the basis of archival, interferometric and single-dish radio data, we have determined the radio spectrum of an elliptical region around the Galactic center of extent 3° semimajor axis (along the Galactic plane) and 1° semiminor axis and a second, rectangular region, also centered on the Galactic center, of extent 1.6°×0.6°. The radio spectra of b..