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Mapping WR140 from infrared spectroscopy and imaging

P. M. Williams·W. P. Varricatt·A. P. Marston·N. M. Ashok
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Abstract

Observations of the 1.083-micron He I line in WR140 (HD 193793) show P-Cygni profiles which varied as the binary system went through periastron passage. A sub-peak appeared on the normally flat-topped emission component and then moved across the profile consistent with its formation in the wind-collision region. Variation of the absorption component provided constraints on the opening angle (theta) of the wind-collision region. Infrared (2-10 micron) images observed with a variety of instruments in 2001-04 resolve the dust cloud formed in 2001, and show it to be expanding at a constant rate. Owing to the high eccentricity of the binary orbit, the dust is spread around the orbital plane in a 'splash' and we compare the dust images with the orientation of the orbit.

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P. M. Williams, W. P. Varricatt, A. P. Marston, N. M. Ashok. 2004-11-16. Mapping WR140 from infrared spectroscopy and imaging. https://arxiv.org/abs/astro-ph/0411440

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