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		| Paper: | 
		Mapping WR140 from Infrared Spectroscopy and Imaging | 
	 
	
		| Volume: | 
		367, Massive Stars in Interactive Binaries | 
	 
	
		| Page: | 
		285 | 
	 
	
		| Authors: | 
		Williams, P.M.; Varricatt, W.P.; Marston, A.P.; Ashok, N.M. | 
	 
	
	
		| Abstract: | 
		Observations of the 1.083-μm 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 (θ) of the wind-collision region. Infrared (2–10-μm) 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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