Colin Littlefield, Peter Garnavich, G. H. Howie Marion, Jozsef Vinko, Colin McClelland, Terrence Rettig, J. Craig Wheeler
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.
View original:
http://arxiv.org/abs/1111.3367
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