Gamma-Ray Excess from the Galactic Center and Supergravity Models
  We analyse the effect of the compression of the dark matter due to the infall of baryons to the galactic center on the gamma-ray flux. In addition, we also consider the effect of non-universal supersymmetric soft terms. This analysis shows that neutralino dark matter   annihilation can give rise to signals largely reachable by   future experiments like GLAST. This is a remarkable result if we realise that direct detection experiments will only be able to cover a small region of the parameter space.   Actually, in this SUGRA framework we have also been able to   fit present excess from EGRET and CANGAROO using different   non-universal scenarios,   and even fit the data from both experiments with only one scenario.   We have also studied the recent HESS data implying a neutralino   heavier than 12 TeV. Because of such a heavy neutralino,   it is not natural to find solutions in the SUGRA framework.   Nevertheless we have carried out a quite model-independent   analysis, and found the conditions required on the particle physics   side to fit the HESS data thanks to dark matter annihilation. 
Y. Mambrini