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arXiv · 0801.3254

Discovery of the radio and X-ray counterpart of TeV Gamma-ray source HESS J1731-347

W. W. Tian·D. A. Leahy·M. Haverkorn·B. Jiang
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Abstract

We discover a faint shell-type radio and X-ray source, G353.6-0.7, associated with HESS J1731-347. G353.6-0.7 is likely an old supernova remnant (SNR), based on radio (0.8 GHz, 1.4 GHz and 5 GHz), infrared (8 $\mu$m from the GLIMPSE Legacy Project and 21 $\mu$m from the Midcourse Space Experiment), and X-ray (0.1 keV - 2.4 keV from the ROSAT survey and 5 - 20 keV from the INTEGRAL survey) data. The SNR, centered at ({\sl l}, {\sl b})=(353.55, -0.65) with a radius of $\sim$ 0.25$^{\circ}$, closely matches the outline of the recently discovered extended TeV source HESS J1731-347, which has no previously identified counterpart. A diffuse X-ray enhancement detected in the ROSAT all-sky survey is coincident with lower half shell of the SNR. Therefore the SNR is the best radio counterpart of both the HESS source and the diffuse X-ray enhancement. G353.6-0.7 has an age of $\sim$ 27000 yrs. Altogether, the new discovery provides the best case that an old SNR emits TeV $\gamma$-rays.

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W. W. Tian, D. A. Leahy, M. Haverkorn, B. Jiang. 2008-01-21. Discovery of the radio and X-ray counterpart of TeV Gamma-ray source HESS J1731-347. https://doi.org/10.1086/589506

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