Searching for Compact Obscured Nuclei in Compton-thick Active Galactic Nuclei
Artikel i vetenskaplig tidskrift, 2025

Compact obscured nuclei (CONs) are heavily obscured infrared cores that have been found in local (ultra-)luminous infrared galaxies. They show bright emission from vibrationally excited rotational transitions of HCN, known as HCN-vib, and are thought to harbor Compton-thick (CT, NH ≥ 1024 cm−2) active galactic nuclei (AGNs) or extreme compact starbursts. We explore the potential evolutionary link between CONs and CT-AGNs by searching for CONs in hard-X-ray-confirmed CT-AGNs from the Great Observatories All-sky LIRG Survey (GOALS). Here, we present new Atacama Large Millimeter/submillimeter Array Band 6 observations that targeted HCN-vib emission in four hard-X-ray-confirmed CT-AGNs. We analyze these objects together with literature HCN-vib measurements of five additional hard-X-ray-confirmed CT-AGNs from the GOALS sample. We do not detect any CONs in this combined sample of nine CT-AGNs. We then explore a proposed evolutionary sequence in which CONs evolve into X-ray-detectable CT-AGNs once outflows and feedback reduce the column densities of the enshrouding gas. We find, however, no evidence of well-developed dense molecular outflows in the observed CT-AGNs. While this could suggest that CT-AGNs are not universally linked to CONs, it could also be explained by a short duty cycle for molecular outflows.

Författare

Makoto A. Johnstone

University of Virginia

Pontificia Universidad Catolica de Chile

G. Privon

College of Liberal Arts and Sciences

National Radio Astronomy Observatory

University of Virginia

Loreto Barcos-Munoz

University of Virginia

National Radio Astronomy Observatory

Aaron S. Evans

National Radio Astronomy Observatory

University of Virginia

Susanne Aalto

Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik

Lee Armus

California Institute of Technology (Caltech)

F. E. Bauer

Instituto Milenio de Astrofísica

Pontificia Universidad Catolica de Chile

L. Blecha

College of Liberal Arts and Sciences

J. S. Gallagher III

Macalester College

University of Wisconsin Madison

Sabine König

Chalmers, Rymd-, geo- och miljövetenskap, Onsala rymdobservatorium

C. Ricci

Universidad Diego Portales

Beijing University of Technology

E. Treister

Pontificia Universidad Catolica de Chile

Cosima Eibensteiner

National Radio Astronomy Observatory

K.L. Emig

National Radio Astronomy Observatory

Kara N. Green

University of Virginia

Devaky Kunneriath

National Radio Astronomy Observatory

Jaya Nagarajan-Swenson

University of Virginia

Alejandro Saravia

University of Virginia

I. Yoon

National Radio Astronomy Observatory

Astrophysical Journal

0004-637X (ISSN) 1538-4357 (eISSN)

Vol. 985 2 259

Ämneskategorier (SSIF 2025)

Atom- och molekylfysik och optik

Astronomi, astrofysik och kosmologi

DOI

10.3847/1538-4357/adcecb

Mer information

Senast uppdaterat

2025-06-09