Modeling the Gamma-Ray Emission of the Galaxy

A model of interstellar gamma-ray emissivity is important for two main reasons. First, the model can help our understanding of gamma-ray emission from the interstellar medium, which is a probe for the study of cosmic rays (distribution, propagation, sources, ..) and for the mapping of the interstellar matter and radiation field. The second reason is that the galactic diffuse gamma-ray emission represents a background over which the point like sources are seen. A detailed modelization of this component is therefore necessary also for the analysis of the gamma-ray point sources.