Gamma rays from molecular clouds

Abstract

It is believed that the observed diffuse gamma ray emission from the galactic plane is the result of interactions between cosmic rays and the interstellar gas. Such emission can be amplified if cosmic rays penetrate into dense molecular clouds. The propagation of cosmic rays inside a molecular cloud has been studied assuming an arbitrary energy and space dependent diffusion coefficient. If the diffusion coefficient inside the cloud is significantly smaller compared to the average one derived for the galactic disk, the observed gamma ray spectrum appears harder than the cosmic ray spectrum, mainly due to the slower penetration of the low energy particles towards the core of the cloud. This may produce a great variety of gamma ray spectra.

Proceeding of "The multi messenger approach to high energy gamma ray sources", Barcelona, June 2006

References in corpus (3)

• Energy spectra of gamma-rays, electrons and neutrinos produced at proton-proton interactions in the very high energy regime
• Discovery of Very-High-Energy Gamma-Rays from the Galactic Centre Ridge
• Gamma Rays from Molecular Clouds

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