Inverse Compton constraints on the Dark Matter e± excesses

Recent results from experiments like PAMELA have pointed to excesses of e± in cosmic rays. If interpreted in terms of Dark Matter annihilations, they imply the existence of an abundant population of e± in the galactic halo at large. We consider the high energy gamma ray fluxes produced by Inverse Compton Scattering of interstellar photons on such e±, and compare them with the available data from EGRET and some preliminary data from FERMI. We consider different observation regions of the sky and a range of DM masses, annihilation channels and DM profiles. We find that large portions of the parameter space are excluded, in particular for DM masses larger than 1 TeV, for leptonic annihilation channels and for benchmark Einasto or NFW profiles. © 2009 Elsevier B.V. All rights reserved