Neutrons from the Galactic centre

Abstract

The cosmic ray anisotropies observed by AGASA and SUGAR from the direction of the Galactic centre may be explained by extremely highenergy neutron production. Diffusive shock acceleration may accelerate protons to the required high energies, with subsequent charge-exchange pp ? nX collisions then producing the neutrons. The Galactic centre gamma ray detections by several experiments provide strong corroborating evidence for this mechanism, with the photons arising from the decay of neutral pions produced through the collisions of the same shock-accelerated proton population. This scenario may be tested in the future through direct detection of the neutrons by AUGER, and indirectly by Galacti..