In a recent multiwavelength study of galaxies at redshift ~ 2 by Daddi et al. (2007a,b) it is shown that galaxies with a Mid-IR excess most likely harbor a Compton-thick AGN, thus bringing to about 1/3 the fraction of z ~ 2 galaxies hosting an AGN. This finding opens a number of intriguing issues concerning the concomitant growth of galaxies and supermassive black holes, AGN feedback, and downsizing, at the cosmic epoch of most intense star formation and nuclear activity.
@article{arxiv.0804.0094,
title = {Witnessing Galaxy-SMBH Co-Evolution at Redshift ~ 2},
author = {Alvio Renzini and Emanuele Daddi},
journal= {arXiv preprint arXiv:0804.0094},
year = {2008}
}
Comments
6 pages, 5 figures, to appear on the proceedings of the conference "Panoramic Views of Galaxy Formation and Evolution", Hayama, Japan, December 11-16, 2007; Ed. Tadayuki Kodama, ASP Conf. Ser. New version (v2) with figure numbering corrected