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A Search for Very Active Stars in the Galaxy

G. Tsarevsky·J. A. De Freitas Pacheco·N. Kardashev·P. De Laverny·Frédéric Thévenin·O. B. Slee·R. A. Stathakis·E. Barsukova·V. Goransky·B. Komberg
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Abstract

We report the first results of a systematic search near the plane of the Galaxy for the so called very active stars (VAS), which are characterized by a hard X-ray spectrum and activity in the radio domain. Candidates with hard X-ray binary-like spectra have been selected from the Bright ROSAT Source Catalogue in the Zone of Avoidance ($| b | < 20{^o}$) and were tentatively identified in GB6/PMM/NVSS radio surveys. Most of them were observed with the ATCA and VLA. Precise radio coordinates have led to unambiguous optical identification for 60 candidates, and a sub-sample of five of themhas been observed with the VLT. Also some discovery and confirmatory spectra were obtained with the AAT (4-m) and BTA (6-m). Spectroscopy with moderate dispersion, made with the FORS1 spectrograph of the VLT has revealed two stellar objects (one of them, VASC J1628-41, is definitivelya binary VAS), one new AGN and two featureless spectrum sources. One of these objects, VASC J1353-66, shows a marginal evidence of proper motion, which, if confirmed, would imply the discovery of a new type of galactic source.

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G. Tsarevsky, J. A. De Freitas Pacheco, N. Kardashev, P. De Laverny, Frédéric Thévenin, O. B. Slee, R. A. Stathakis, E. Barsukova, V. Goransky, B. Komberg. 2005-02-18. A Search for Very Active Stars in the Galaxy. https://doi.org/10.1051/0004-6361%3A20042274

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