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		| Paper: | 
		Exploring the Evolutionary Status of z≈2 SCUBA Galaxies Hosting Active Galactic Nuclei | 
	 
	
		| Volume: | 
		379, Cosmic Frontiers | 
	 
	
		| Page: | 
		169 | 
	 
	
		| Authors: | 
		Alexander, D.M. | 
	 
	
	
		| Abstract: | 
		Deep SCUBA surveys have uncovered a large population of dust-enshrouded star-forming galaxies at z ≈ 2. Using the ultra-deep 2 Ms Chandra Deep Field-North survey we recently showed that a large fraction of these systems are also undergoing intense black-hole growth. Here we provide constraints on the properties of the black holes in SCUBA galaxies using the virial black-hole mass estimator and show that typical SCUBA galaxies host black holes with MBH ≈ 5 × 107 M⊙ that are accreting at ≈ 20% of the Eddington limit. We discuss these results in the context of the joint black-hole–galaxy growth for the progenitors of today’s massive galaxies and find that the black holes in SCUBA galaxies are up-to an order of magnitude smaller than those found for comparably massive galaxies in the local Universe. This implies that these high-z sources will need to undergo considerable additional black-hole growth before lying on the locally defined black-hole–spheroid mass relationship, in qualitative agreement with the results presented in Borys et al. (2005). | 
	 
	
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