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		| Paper: | 
		Similarities in the Structure of the Circumstellar Environments of B[e] Supergiants and Yellow Hypergiants | 
	 
	
		| Volume: | 
		508, The B[e] Phenomenom: Forty Years of Studies | 
	 
	
		| Page: | 
		239 | 
	 
	
		| Authors: | 
		Aret, A.; Kolka, I.; Kraus, M.; Maravelias, G. | 
	 
	
	
		| Abstract: | 
		Yellow hypergiants (YHGs) and B[e] supergiants (B[e]SGs), though in different  phases in their evolution, have many features in common. This is partly due to the fact that both types of objects undergo strong, often asymmetric mass loss, and the ejected material accumulates in shells, rings, or disk-like  structures, giving rise to emission from warm molecules and dust.  We performed an optical spectroscopic survey of northern  Galactic emission-line stars aimed at identifying tracers for the  structure and kinematics of circumstellar environments. We identified two sets of lines, [O I] and [Ca II], which originate from the disks of B[e]SGs. The same set of lines is observed in V1302 Aql and  V509 Cas, which are both hot YHGs. While V1302 Aql is known to have a disk-like  structure, the kinematical broadening of the lines in V509 Cas suggests a  Keplerian disk or ring around this star like their hotter B[e]SG counterparts. | 
	 
	
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