Searching for hidden Wolf-Rayet stars in the Galactic Plane – 15 new Wolf-Rayet stars
نویسندگان
چکیده
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 (midinfrared) 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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