Five WC9 stars discovered in the AAO/UKST H-alpha Survey

E. C. Hopewell; M. J. Barlow; J. E. Drew; Y. C. Unruh; Q. A. Parker; M. J. Pierce; P. A. Crowther; C. Knigge; S. Phillipps; A. A. Zijlstra

doi:10.1111/j.1365-2966.2005.09487.x

arXiv · astro-ph/0508187

Five WC9 stars discovered in the AAO/UKST H-alpha Survey

E. C. Hopewell·M. J. Barlow·J. E. Drew·Y. C. Unruh·Q. A. Parker·M. J. Pierce·P. A. Crowther·C. Knigge·S. Phillipps·A. A. Zijlstra

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Abstract

We report the discovery of 5 massive Wolf-Rayet (WR) stars resulting from a programme of follow-up spectroscopy of candidate emission line stars in the AAO/UKST Southern Galactic Plane H-alpha survey. The 6195-6775 angstrom spectra of the stars are presented and discussed. A WC9 class is assigned to all 5 stars through comparison of their spectra with those of known late-type WC stars, bringing the known total number of Galactic WC9 stars to 44. Whilst three of the five WC9 stars exhibit near infrared (NIR) excesses characteristic of hot dust emission -- as seen in the great majority of known WC9 stars -- we find that two of the stars show no discernible evidence of such excesses. This increases the number of known WC9 stars without NIR excesses to 7. Reddenings and distances for all 5 stars are estimated.

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E. C. Hopewell, M. J. Barlow, J. E. Drew, Y. C. Unruh, Q. A. Parker, M. J. Pierce, P. A. Crowther, C. Knigge, S. Phillipps, A. A. Zijlstra. 2005-08-08. Five WC9 stars discovered in the AAO/UKST H-alpha Survey. https://doi.org/10.1111/j.1365-2966.2005.09487.x

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