Gravitational Effects on Particle Dark Matter and Indirect Detection

The annihilation signal of particle dark matter can be strongly enhanced in over-dense regions such as close to the Galactic centre. We summarize some of our recent results on fluxes of gamma-rays, neutrinos and radio waves under different assumptions for the largely uncertain dark matter profile which close to the Galactic centre is strongly influenced by the super-massive black hole. We apply this to two particle dark matter scenarios, namely the case of neutralinos in supersymmetric scenarios and the lowest Kaluza-Klein excitation of the hyper-charge gauge boson in scenarios where the Standard Model fields propagate in one microscopic extra dimension.