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arXiv · 0710.2017

Discovery of very high energy gamma-ray emission in the W 28 (G6.4-0.1) region, and multiwavelength comparisons

H. E. S. S. Collaboration·:·G. Rowell·E. Brion·O. Reimer·Y. Moriguchi·Y. Fukui·A. Djannati-Ataï·S. Funk
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Abstract

H.E.S.S. observations of the old-age (>10^4yr; ~0.5deg diameter) composite supernova remnant (SNR) W 28 reveal very high energy (VHE) gamma-ray emission situated at its northeastern and southern boundaries. The northeastern VHE source (HESS J1801-233) is in an area where W 28 is interacting with a dense molecular cloud, containing OH masers, local radio and X-ray peaks. The southern VHE sources (HESS J1800-240 with components labelled A, B and C) are found in a region occupied by several HII regions, including the ultracompact HII region W 28A2. Our analysis of NANTEN CO data reveals a dense molecular cloud enveloping this southern region, and our reanalysis of EGRET data reveals MeV/GeV emission centred on HESS J1801-233 and the northeastern interaction region.

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H. E. S. S. Collaboration, :, G. Rowell, E. Brion, O. Reimer, Y. Moriguchi, Y. Fukui, A. Djannati-Ataï, S. Funk. 2007-10-10. Discovery of very high energy gamma-ray emission in the W 28 (G6.4-0.1) region, and multiwavelength comparisons. https://arxiv.org/abs/0710.2017

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