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arXiv · 1101.2468

Newly Discovered Wolf-Rayet and Weak Emission-Line Central Stars of Planetary Nebulae

Kyle DePew·Quentin A. Parker·Brent Miszalski·Orsola De Marco·David J. Frew·Agnes Acker·Anna V. Kovacevic·Rob G. Sharp
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Abstract

We present spectra of 32 previously unpublished confirmed and candidate Wolf-Rayet ([WR]) and weak emission-line (WELS) central stars of planetary nebulae (CSPNe). Eighteen stars have been discovered in the Macquarie/AAO/Strasbourg H-Alpha (MASH) PN survey sample, and we have also uncovered 14 confirmed and candidate [WR]s and WELS among the CSPNe of previously known PNe. Spectral classifications have been undertaken using both the Acker & Neiner and Crowther, De Marco & Barlow schemes. Twenty-two members in this sample are identified as probable [WR]s; the remaining 10 appear to be WELS. Observations undertaken as part of the MASH spectroscopic survey have now increased the number of known [WR]s by ~30 per cent. This will permit a better analysis of [WR] subclass distribution, metallicity effects, and evolutionary sequences in these uncommon objects.

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Kyle DePew, Quentin A. Parker, Brent Miszalski, Orsola De Marco, David J. Frew, Agnes Acker, Anna V. Kovacevic, Rob G. Sharp. 2011-01-13. Newly Discovered Wolf-Rayet and Weak Emission-Line Central Stars of Planetary Nebulae. https://doi.org/10.1111/j.1365-2966.2011.18337.x

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