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		| Paper: | 
		Detection of an 0.1 pc Dust Shell of the Carbon Star U Hydrae in Optical Light | 
	 
	
		| Volume: | 
		378, Why Galaxies Care About AGB Stars: Their Importance as Actors and Probes | 
	 
	
		| Page: | 
		305 | 
	 
	
		| Authors: | 
		Izumiura, H.; Nakada, Y.; Hashimoto, O.; Mito, H.; Hayashi, T. | 
	 
	
	
		| Abstract: | 
		A very extended circumstellar shell is detected around the carbon star U Hya in the V band. The shell looks circular and the radial profile of its brightness shows a clear maximum at ~115″ followed by a rapid decline to the rim at ~130″ (0.1 pc), which indicates the shell is probably spherical and geometrically thin. The dust mass in the shell is estimated to be ~10−5 M⊙ assuming some simple dust grain properties and that the shell is seen in the scattered light of the central star. Because no such extended CO gas shell is present in U Hya, this becomes the first instance of an opitical dust shell detected far beyond the CO photo-dissociation radius in an AGB star. | 
	 
	
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