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Searching for hidden Wolf-Rayet stars in the Galactic Plane - 15 new Wolf-Rayet stars

L. J. Hadfield·S. D. Van Dyk·P. W. Morris·J. D. Smith·A. P. Marston·D. E. Peterson
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Abstract

We report the discovery of fifteen previously unknown Wolf-Rayet (WR) stars found as part of an infrared broad-band study of candidate WR stars in the Galaxy. We have derived an empirically-based selection algorithm which has selected ~5000 WR candidate stars located within the Galactic Plane drawn from the GLIMPSE (mid-infrared) and 2MASS (near-infrared) catalogues. Spectroscopic follow-up of 184 of these reveals eleven WN and four WC-type WR stars. Early WC subtypes are absent from our sample and none show evidence for circumstellar dust emission. Of the candidates which are not WR stars, ~120 displayed hydrogen emission line features in their spectra. Spectral features suggest that the majority of these are in fact B supergiants/hypergiants, ~40 of these are identified Be/B[e] candidates. Here, we present the optical spectra for six of the newly-detected WR stars, and the near-infrared spectra for the remaining nine of our sample. With a WR yield rate of ~7% and a massive star detection rate of ~65%, initial results suggest that this method is one of the most successful means for locating evolved, massive stars in the Galaxy.

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L. J. Hadfield, S. D. Van Dyk, P. W. Morris, J. D. Smith, A. P. Marston, D. E. Peterson. 2006-12-20. Searching for hidden Wolf-Rayet stars in the Galactic Plane - 15 new Wolf-Rayet stars. https://doi.org/10.1111/j.1365-2966.2007.11424.x

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