Finding dusty AGNs from the JWST CEERS survey with mid-infrared photometry

TL;DR

This study uses JWST mid-infrared photometry to identify and analyze obscured AGNs in the CEERS survey, revealing new insights into their luminosity contributions and distribution across redshifts.

Contribution

First application of JWST mid-infrared data to identify obscured AGNs, expanding the understanding of AGN populations beyond ultra-luminous infrared galaxies.

Findings

Identified 42 AGN candidates using SED fitting.

Found no clear redshift or luminosity dependence in AGN fractions.

Extended AGN studies to less luminous infrared galaxies.

Abstract

The nature of the interaction between active galactic nuclei (AGNs) and their host galaxies remains an unsolved question. Therefore, conducting an AGN census is valuable to AGN research. Nevertheless, a significant fraction of AGNs are obscured by their environment, which blocks UV and optical emissions due to the dusty torus surrounding the central supermassive black hole (SMBH). To overcome this challenge, mid-infrared (IR) surveys have emerged as a valuable tool for identifying obscured AGNs, as the obscured light is re-emitted in this range. With its high sensitivity, the James Webb Space Telescope (JWST) uncovered more fainter objects than previous telescopes. By applying the SED fitting, this work investigates AGN candidates in JWST Cosmic Evolution Early Release Science (CEERS) fields. We identified 42 candidates, 30 of them are classified as composites ($0.2\leq f_{\rm AGN, IR}< 0.5$), and 12 of them are AGNs ($f_{\rm AGN, IR}\geq 0.5$). We report the AGN luminosity contributions and AGN number fractions as a function of redshift and total infrared luminosity, showing that previously reported increasing relations are not apparent in our sample due to the sample size. We also extend the previous results on ultra-luminous infrared galaxies (ULIRGs, $L_{\rm TIR}\geq 10^{12} L_{\odot}$) to less luminous AGNs, highlighting the power of JWST.