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arXiv · 0904.2887

Molecular Clouds as Cosmic-Ray Barometers

S. Casanova·F. A. Aharonian·Y. Fukui·S. Gabici·D. I. Jones·A. Kawamura·T. Onishi·G. Rowell·K. Torii·H. Yamamoto
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Abstract

The advent of high sensitivity, high resolution gamma-ray detectors, together with a knowledge of the distribution of the atomic hydrogen and especially of the molecular hydrogen in the Galaxy on sub-degree scales creates a unique opportunity to explore the flux of cosmic rays in the Galaxy. We here present the new data on the distribution of the molecular hydrogen from a large region of the inner Galaxy obtained by the NANTEN Collaboration. We then introduce a methodology which aims to provide a test bed for current and future gamma-ray observatories to explore the cosmic ray flux at various positions in our Galaxy. In particular, for a distribution of molecular clouds, as provided by the NANTEN survey, and local cosmic ray density as measured at the Earth, we estimate the expected GeV to TeV gamma-ray signal, which can then be compared with observations and use to test the cosmic ray flux.

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S. Casanova, F. A. Aharonian, Y. Fukui, S. Gabici, D. I. Jones, A. Kawamura, T. Onishi, G. Rowell, K. Torii, H. Yamamoto. 2010-04-19. Molecular Clouds as Cosmic-Ray Barometers. https://doi.org/10.1093/pasj%2F62.3.769

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