A Catalog of AGN Host Galaxies Observed with HST/ACS: Correlations between Star Formation and AGN Activity

TL;DR

This paper introduces a comprehensive catalog of 2585 AGN host galaxies observed with HST/ACS, analyzing their star formation and AGN activity correlations across redshifts 0.2 to 2.5.

Contribution

The study provides a new multi-wavelength catalog with derived galaxy and AGN properties, revealing links between star formation, AGN luminosity, and stellar mass.

Findings

AGN hosts tend to lie below the star-forming main sequence.

X-ray-selected AGN hosts are more offset from the main sequence than IR-selected.

There is a positive correlation between star formation rate and AGN luminosity.

Abstract

We present the Advanced Camera for Surveys Active Galactic Nuclei (ACS-AGN) Catalog, a catalog of 2585 active galactic nucleus (AGN) host galaxies that are at redshifts 0.2<z<2.5 and that were imaged with the Hubble Space Telescope's Advanced Camera for Surveys (ACS). Using the ACS General Catalog (ACS-GC) as our initial sample, we select an AGN subsample using Spitzer and Chandra data along with their respective established AGN selection criteria. We then gather further multi-wavelength photometric data in order to construct spectral energy distributions (SEDs). Using these SEDs we are able to derive multiple AGN and host galaxy properties, such as star formation rate, AGN luminosity, stellar mass, and nuclear column density. From these data, we show that AGN host galaxies tend to lie below the star-forming main sequence, with X-ray-selected AGN host galaxies being more offset than IR-selected AGN host galaxies. This suggests that there is some process, possibly negative feedback, in AGN host galaxies causing decreased star formation. We also demonstrate that there is a positive trend between star formation rate and AGN luminosity in AGN host galaxies, in individual redshift bins and across all redshift bins, and that both are correlated with the stellar mass of their galaxies. This points towards an underlying link between the stellar mass, stellar growth, and SMBH growth in a galaxy.