Evidence for a discrete source contribution to low-energy continuum Galactic gamma-rays

Abstract

Models for the diffuse Galactic continuum emission and synchrotron radiation show that it is difficult to reproduce observations of both of these from the same population of cosmic-ray electrons. This indicates that an important contributor to the emission below 10 MeV could be an unresolved point-source population. We suggest that these could be Crab-like sources in the inner Galaxy. Alternatively a sharp upturn in the electron spectrum below 200 MeV is required.