The diffuse galactic EGRET gamma ray data show a clear excess for energiesabove 1 GeV in comparison with the expectations from conventional galacticmodels. This excess shows all the features expected from Dark Matter WIMPAnnihilation: a)it is present and has the same spectrum in all sky directions,not just in the galactic plane, as expected for WIMP annihilation b) it showsan interesting substructure in the form of a doughnut shaped ring at 14 kpcfrom the centre of the galaxy, where a ring of stars indicated the probable infallof a dwarf galaxy. From the spectral shape of the excess the WIMP mass isestimated to be between 50 and 100 GeV, while from the intensity the haloprofile is reconstructed, which is shown to explain the peculiar change of slopein the rotation curve at about 11 kpc (due to the ring of DM at 14 kpc). Recently it was claimed by Bergstrom et al. that the DM interpretation ofthe EGRET gamma ray excess is excluded by the antiproton fluxes, since intheir propagation model with isotropic diffusion the flux of antiprotons wouldbe far beyond the observed flux. However, the propagation can be largelyanisotropic, because of the convection of particles perpendicular to the discand inhomogeneities in the local environment. It is shown that anisotropicpropagation can reduce the antiproton yield by an order of magnitude, whilestill being consistent with the B/C ratio. Therefore it is hard to use antiprotonsto search for light DM particles, which yield a similar antiproton spectrum asthe background, but the antiprotons are a perfect means to tune the manydegenerate parameters in the propagation models.
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