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		| Paper: | 
		QSO Absorption Lines and the Halos of Cluster Galaxies | 
	 
	
		| Volume: | 
		165, The Third Stromlo Symposium: The Galactic Halo | 
	 
	
		| Page: | 
		192 | 
	 
	
		| Authors: | 
		Francis, Paul J.; Wilson, Greg M.; Woodgate, Bruce E. | 
	 
	
	
		| Abstract: | 
		In the local universe, most QSO absorption-lines seem to arise from gas in extended ~ 100 kpc halos around spiral galaxies. We present evidence that at high redshift, at least some absorption lines come from different sources: the gas is associated not with spiral galaxy halos but with the intra-cluster medium of proto-galaxy clusters. This gas, which is neutral and lumpy, may form a true intra-cluster medium, but it is more likely to be associated with the halos of young elliptical galaxies. This gas may turn into the X-ray emitting intra-cluster medium of present-day rich galaxy clusters. | 
	 
	
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