Gamma Ray Astronomy and Baryonic Dark Matter

Recently, Dixon et al. (1998) have re-analyzed the EGRET data, finding a statistically significant diffuse γ-ray emission from the galactic halo. We show that this emission can naturally be explained within a previously-proposed model for baryonic dark matter, in which γ-rays are produced through the interaction of high-energy cosmic-ray protons with cold H2 clouds clumped into dark clusters these dark clusters supposedly populate the outer galactic halo and can show up in microlensing observations. Our estimate for the halo γ-ray flux turns out to be in remarkably good agreement with the discovery by Dixon et al. (1998). We also address future prospects to test our predictions. Subject headings: dark matter diffuse radiation Galaxy: halo gamma rays: theory