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arXiv · 1112.2655

The HI absorption distance of HESS J1943+213 favours its extragalactic nature

Denis leahy·Wenwu Tian
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Abstract

The H.E.S.S. collaboration (Abramowski et al. 2011) dicovered a new TeV point-like source HESS J1943+213 in the Galactic plane and suggested three possible low-energy-band counterparts: a $γ$-ray binary, a pulsar wind nebula (PWN), or a BL Lacertae object. We measure the distance to the radio counterpart G57.76-1.29 of HESS J1943+213. We analyze Very Large Array observations to obtain a reliable HI absorption spectrum.The resulting distance limit is $\ge$ 16 kpc. This distance strongly supports that HESS J1943+213 is an extragalactic source, consistent with the preferred counterpart of the HESS collaboration.

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Denis leahy, Wenwu Tian. 2012-01-26. The HI absorption distance of HESS J1943+213 favours its extragalactic nature. https://doi.org/10.1051/0004-6361%2F201118633

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