Galactic γ and radio synchrotron radiation

Abstract

The galactic γ-radiation and radio synchrotron radiation contains information on the distribution of cosmic-ray particles, magnetic field and gas throughout the Galaxy. We report here a new all-sky survey of 408-MHz radio continuum which has been used to compare the distributions of radio and γ-ray emission, with the former convolved to the response function of the COS B γ-ray detector. The overall similarity of the longitude profiles suggests that the bulk of the γ-ray emission is from the interstellar medium rather than discrete sources. On a large scale in the galactic plane the two emissivities seem to be similarly distributed, although in detail the γ-ray emission is more clumpy.