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arXiv · 1401.3354

SNR G349.7+0.2: A gamma-ray source in the far 3 kpc arm of the Galactic center

W. W. Tian·D. A Leahy
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Abstract

We analyze the HI absorption profile for TeV Supernova Remnant (SNR) G349.7+0.2 based on updated knowledge of the inner Galaxy's structure. We significantly revise its kinematic distance from the previous ~ 22 kpc to ~11.5 kpc, indicating it is in the far 3 kpc arm of the Galactic center. We give a revised age of ~ 1800 year for G349.7+0.2 which has a low explosion energy of ~ 2.5 x 10^50 ergs. This removes G349.7+0.2 from the set of brightest SNRs in radio, X-ray to gamma-ray wavebands and helps understand gamma-ray emission originating from this remnant better. However, one needs to use caution for old kinematic distances of Galactic objects (e.g. SNRs, Pulsars and HII regions) in the range of -12 degree =< l =< 12 degree and having distance estimates of >= 5.5 kpc.

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W. W. Tian, D. A Leahy. 2014-01-14. SNR G349.7+0.2: A gamma-ray source in the far 3 kpc arm of the Galactic center. https://doi.org/10.1088/2041-8205%2F783%2F1%2Fl2

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