Cosmic rays, the metallicity gradient and the mass of molecular gas in the Galaxy
- 1 August 1982
- journal article
- Published by IOP Publishing in Journal of Physics G: Nuclear Physics
- Vol. 8 (8), 1141-1154
- https://doi.org/10.1088/0305-4616/8/8/017
Abstract
Information on the metallicity gradient in the Galaxy is assessed and used to make a new estimate of the distribution of molecular hydrogen (H2) in the Galaxy. it is found that the radial distribution of H2 is rather different than thought hitherto and not too far from that of atomic hydrogen (H1). Gamma-ray data above 35 MeV from the SAS II and COS B satellites have been used, together with the estimated masses of both H2 and H1, to determine the galactic distribution of cosmic rays under the assumption that the flux of gamma rays from unresolved sources is negligible. It is found that the intensity distribution (or electrons of several hundred MeV and protons of a few GeV) is similar to that of supernova remnants.Keywords
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