Presentation #504.06 in the session “AGN and Host Galaxies”.
The observational evidence of active galactic nuclei (AGN)-driven galaxy quenching is still elusive. Observations both in the local Universe and at high redshifts have extensively shown that the host galaxies of X-ray and optically selected AGNs tend (relative to the non-AGN hosts) to be green and compact. Such correlations between AGN activities and host galaxy color and morphology seem to suggest a causation between AGNs and galaxy quenching. With X-ray selection only, however, one can miss a population of highly obscured AGNs. It remains unknown that how this missed population would affect our understanding of AGN quenching. To get a more comprehensive picture of radiative AGN effects on galaxy properties, we therefore conduct a combined study of X-ray and IR selected AGNs at z≈2 in the CANDELS/GOODS, aiming to look for the evidence of AGN quenching. We compare both star formation and morphological properties of non-AGNs and AGNs. We show that (see Figure), while X-ray AGNs tend to be green and compact, IR AGNs occupy a different parameter space which is similar as normal star-forming galaxies. The combined view of X-ray and IR selected AGNs therefore shows no clear observational evidence of on-going AGN activities driving the galaxy transition from the blue cloud (star-forming) to the red sequence (quiescent).