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arXiv · 1111.3367

Discovery of a Wolf-Rayet Star Through Detection of its Photometric Variability

Colin Littlefield·Peter Garnavich·G. H. Howie Marion·Jozsef Vinko·Colin McClelland·Terrence Rettig·J. Craig Wheeler
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Abstract

We report the serendipitous discovery of a heavily reddened Wolf-Rayet star that we name WR142b. While photometrically monitoring a cataclysmic variable, we detected weak variability in a nearby field star. Low-resolution spectroscopy revealed a strong emission line at 7100 Ang., suggesting an unusual object and prompting further study. A spectrum taken with the Hobby-Eberly Telescope confirms strong HeII emission and a NIV 7112 Ang. line consistent with a nitrogen-rich Wolf-Rayet star of spectral class WN6. Analysis of the HeII line strengths reveals no detectable hydrogen in WR142b. A blue-sensitive spectrum obtained with the Large Binocular Telescope shows no evidence for a hot companion star. The continuum shape and emission line ratios imply a reddening of E(B-V)=2.2 to 2.5 mag. If not for the dust extinction, this new Wolf-Rayet star could be visible to the naked eye.

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Colin Littlefield, Peter Garnavich, G. H. Howie Marion, Jozsef Vinko, Colin McClelland, Terrence Rettig, J. Craig Wheeler. 2011-11-14. Discovery of a Wolf-Rayet Star Through Detection of its Photometric Variability. https://doi.org/10.1088/0004-6256/143/6/136

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