X-ray selected AGN Hosts are Similar to Inactive Galaxies out to z=3: Results from CANDELS/CDF-SAstrophysical Journal (2006)
AbstractWe use multi-band high-resolution photometry in the 4 MSec Chandra Deep Field-South (CDF-S), in particular imaging from the Cosmic Assembly Near-IR Deep Legacy Survey (CANDELS), to explore the nuclear and extended colors, color gradients and stellar populations of X-ray selected AGN host galaxies out to z=3. Based on a study of their central light, we develop X-ray based criteria to exclude objects with strong AGN contamination. We use stellar masses from the FIREWORKS database to understand and account for stellar mass selection effects, and carefully study, for the first time, the resolved host galaxy properties of AGNs at z~2 in the rest-frame optical light without substantial nuclear contamination. We find that AGN hosts span a large range of stellar masses, colors and color gradients at these redshifts. In terms of their colors and stellar population properties, they are very similar to inactive galaxies of the same stellar mass. At z~1, we find a slightly narrower range in host colors compared to inactive galaxies, as well as hints of more recent star-formation. These differences are weaker or non-existent among AGN hosts at z~2. Finally, we find that AGNs show flatter color gradients compared to inactive galaxies, with the degree of flatness correlating with AGN luminosity, implying that, even among obscured AGNs with no clear nuclear contamination, central photometry can be affected by nuclear activity, perhaps through scattered AGN light. We discuss the importance of AGN driven feedback in the quenching of galaxies at z>~1 and speculate on possible evolution in the relationship between black hole accretion and the host galaxy at high redshifts.
- galaxies: active galaxies
Citation InformationD. J. Rosario, M. Mozena, S. Wuyts, K. Nandra, et al.. "X-ray selected AGN Hosts are Similar to Inactive Galaxies out to z=3: Results from CANDELS/CDF-S" Astrophysical Journal (2006)
Available at: http://works.bepress.com/mauro_giavalisco/10/