Cosmic rays and molecular clouds

Abstract

This paper deals with the cosmic-ray penetration into molecular clouds and with the related gamma--ray emission. High energy cosmic rays interact with the dense gas and produce neutral pions which in turn decay into two gamma rays. This makes molecular clouds potential sources of gamma rays, especially if they are located in the vicinity of a powerful accelerator that injects cosmic rays in the interstellar medium. The amplitude and duration in time of the cosmic--ray overdensity around a given source depend on how quickly cosmic rays diffuse in the turbulent galactic magnetic field. For these reasons, gamma-ray observations of molecular clouds can be used both to locate the sources of cosmic rays and to constrain the properties of cosmic-ray diffusion in the Galaxy.

To appear in the proceedings of the San Cugat Forum on Astrophysics 2012, 27 pages, 10 figures

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Cited by in corpus (7)

• Non-linear diffusion of cosmic rays escaping from supernova remnants - I. The effect of neutrals
• Constraining the properties of the magnetic turbulence in the Geminga region using HAWC $\gamma$-ray data
• Cosmic ray penetration in diffuse clouds
• The interstellar medium in young supernova remnants: key to the production of cosmic X-rays and $\gamma$-rays
• New Constraints on Cosmic Particle Populations at the Galactic Center using X-ray Observations of the Molecular Cloud Sagittarius B2
• Energy estimation of high energy particles associated with the SS433/W50 system through radio observation at 1.4 GHz
• Acceleration of cosmic rays and gamma-ray emission from supernova remnant/molecular cloud associations