Constraints on top-down models for the origin of UHECRs from the Pierre Auger Observatory data

THE PIERRE AUGER COLLABORATION (AUTOR 384 DE 427); M. J. TUEROS

Mérida, México

Conferencia; 30th International Cosmic Ray Conference; 2007

Instituto de Geofísica, UNAM

Taking into account the Pierre Auger Observatory limits on the photon fraction among the highest energy cosmic rays, we show that the models based on the decay of super-heavy dark matter in the halo of our Galaxy are essentially excluded from being the sources of UHECRs unless their contribution becomes significant only above ~100 EeV. Some top-downmodels based on topological defects are however compatible with the current data and maybe best constrained in the future by the high-energy neutrino flux limit.