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arXiv · 1307.4484

Interstellar gas towards CTB 37A and the TeV gamma-ray source HESS J1714-385

Nigel I. Maxted·Gavin P. Rowell·Bruce R. Dawson·Michael G. Burton·Yasuo Fukui·Andrew Walsh·Akiko Kawamura·Hirotaka Horachi·Hidetoshi Sano·Satoshi Yoshiike·Tatsuya Fukuda
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Abstract

Observations of dense molecular gas towards the supernova remnants CTB 37A (G348.5+0.1) and G348.5-0.0 were carried out using the Mopra and Nanten2 radio telescopes. We present CO(2-1) and CS(1-0) emission maps of a region encompassing the CTB 37A TeV gamma-ray emission, HESS J1714-385, revealing regions of dense gas within associated molecular clouds. Some gas displays good overlap with gamma-ray emission, consistent with hadronic gamma-ray emission scenarios. Masses of gas towards the HESS J1714-385 TeV gamma-ray emission region were estimated, and were of the order of 10^3-10^4 solar masses. In the case of a purely hadronic origin for the gamma-ray emission, the cosmic ray flux enhancement is ~80-1100 times the local solar value. This enhancement factor and other considerations allow a discussion of the age of CTB 37A, which is consistent with ~10^4 yr.

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Nigel I. Maxted, Gavin P. Rowell, Bruce R. Dawson, Michael G. Burton, Yasuo Fukui, Andrew Walsh, Akiko Kawamura, Hirotaka Horachi, Hidetoshi Sano, Satoshi Yoshiike, Tatsuya Fukuda. 2013-07-17. Interstellar gas towards CTB 37A and the TeV gamma-ray source HESS J1714-385. https://doi.org/10.1093/mnras/stt1159

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