Gamma Rays from Molecular Clouds
نویسندگان
چکیده
High energy γ-rays from individual giant molecular clouds contain unique information about the hidden sites of acceleration of galactic cosmic rays, and provide a feasible method for study of propagation of cosmic rays in the Galactic Disk on scales ≤ 100 pc. I discuss the spectral features of π-decay γ-radiation from clouds/targets located in proximity of relatively young proton accelerators, and speculate that such “accelerator+target” systems in our Galaxy can be responsible for a subset of unidentified EGRET sources. Also, I argue that the recent observations of high energy γ-rays from the Orion complex contain evidence that the level of the “sea” of galactic cosmic rays may differ significantly from the flux and the spectrum of local (directly detected) particles.
منابع مشابه
Gamma rays from molecular clouds
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 ...
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