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		| Paper: | 
		Shells and Bipolar Structures around B[e] Stars | 
	 
	
		| Volume: | 
		355, Stars With the B[e] Phenomenon | 
	 
	
		| Page: | 
		189 | 
	 
	
		| Authors: | 
		Marston, A.P.; McCollum, B. | 
	 
	
	
		| Abstract: | 
		The position of B[e] stars in the upper left part of the Hertzsprung- Russell diagram provides a quandary. Are these stars young stars evolving on to the main sequence or old stars that are evolving off of it? Spectral characteristics suggest B[e] stars may be placed into five subclasses and are not a homogeneous set. The sub-classification is believed to coincide with varying origins and evolution. However, the evolutionary connection of B[e] stars - and notably sgB[e] stars - to other evolved massive stars is unclear. In order to attempt to provide insight into the evolutionary past of B[e] stars we have performed a Hα narrowband CCD imaging survey of B[e] stars in the northern hemisphere. Prior to the current work, no emission-line survey of B[e] stars had yet performed and only two B[e] stars appear to have a shell nebula as seen in the Digital Sky Survey. Of nebulae around B[e] stars, only the nebula around MWC137 has been extensively observed previously. In this presentation we report the findings of our survey of the environments of 26 B[e] stars. Of the objects surveyed, 7 show bipolar or uni-polar structures up to 15′ across, 5 show faint, large or filamentary shells and 2 are compact planetary nebula-type systems. The most spectacular system observed is a large bipolar structure associated with MWC314. | 
	 
	
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