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arXiv · 1110.5039

VLBI search for the radio counterpart of HESS J1943+213

K. E. Gabanyi·G. Dubner·E. Giacani·Z. Paragi·S. Frey·Y. Pidopryhora
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Abstract

HESS J1943+213, a TeV point source close to the Galactic plane recently discovered by the H.E.S.S. collaboration, was proposed to be an extreme BL Lacertae object, though a pulsar wind nebula (PWN) nature could not be completely discarded. To investigate its nature, we performed high-resolution radio observations with the European Very Long Baseline Interferometry Network (EVN) and reanalyzed archival continuum and H {\sc i} data. The EVN observations revealed a compact radio counterpart of the TeV source. The low brightness temperature and the resolved nature of the radio source are indications against the beamed BL Lacertae hypothesis. The radio/X-ray source appears immersed in a $\sim$ 1\arcmin elliptical feature suggesting a possible galactic origin (PWN nature) for the HESS source. We found that HESS\,J1943+213 is located in the interior of a $\sim1\degr$ diameter H {\sc i} feature, and explored the possibility of they being physically related.

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K. E. Gabanyi, G. Dubner, E. Giacani, Z. Paragi, S. Frey, Y. Pidopryhora. 2012-12-18. VLBI search for the radio counterpart of HESS J1943+213. https://doi.org/10.1088/0004-637x%2F762%2F1%2F63

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