AMUSE-Antlia. I. Nuclear X-Ray Properties of Early-type Galaxies in a Dynamically Young Galaxy Cluster

Hu, Zhensong; Su, Yuanyuan; Li, Zhiyuan; Hess, Kelley M.; Kraft, Ralph P.; Forman, William R.; Nulsen, Paul E.J.; Sridhar, Sarrvesh S.; Stroe, Andra; Baek, Junhyun; Chung, Aeree; Grupe, Dirk; Chen, Hao; Irwin, Jimmy A.; Jones, Christine; Randall, Scott W.; Roediger, Elke

Abstract

To understand the formation and growth of supermassive black holes (SMBHs) and their coevolution with host galaxies, it is essential to know the impact of environment on the activity of active galactic nuclei (AGNs). We present new Chandra X-ray observations of nuclear emission from member galaxies in the Antlia cluster, the nearest non-cool core and the nearest merging galaxy cluster, residing at D = 35.2 Mpc. Its inner region, centered on two dominant galaxies NGC 3268 and NGC 3258, has been mapped with three deep Chandra ACIS-I pointings. Nuclear X-ray sources are detected in 7/84 (8.3%) early-type galaxies (ETG) and 2/8 (25%) late-type galaxies with a median detection limit of 8 × 1038 erg s−1. All nuclear X-ray sources but one have a corresponding radio continuum source detected by MeerKAT at the L band. Nuclear X-ray sources detected in early-type galaxies are considered the genuine X-ray counterpart of low-luminosity AGN. When restricted to a detection limit of log ( L X / erg s − 1 ) ≥ 38.9 and a stellar mass of 10 ≤ log ( M ⋆ / M ⊙ ) < 11.6 , six of 11 ETGs are found to contain an X-ray AGN in Antlia, exceeding the AGN occupation fraction of 7/39 (18.0%) and 2/12 (16.7%) in the more relaxed, cool core clusters, Virgo and Fornax, respectively, and rivaling that of the AMUSE-Field ETG of 27/49 (55.1%). Furthermore, more than half of the X-ray AGN in Antlia is hosted by its younger subcluster, centered on NGC 3258. We believe that this is because SMBH activity is enhanced in a dynamically young cluster compared to relatively relaxed clusters.

Citation

Hu, Z., Su, Y., Li, Z., Hess, K. M., Kraft, R. P., Forman, W. R., …Roediger, E. (2023). AMUSE-Antlia. I. Nuclear X-Ray Properties of Early-type Galaxies in a Dynamically Young Galaxy Cluster. The Astrophysical journal, 956(2), Article 104. https://doi.org/10.3847/1538-4357/acf292

• Journal Article Type: Article
• Acceptance Date: Aug 20, 2023
• Online Publication Date: Oct 12, 2023
• Publication Date: Oct 20, 2023
• Deposit Date: Nov 11, 2023
• Publicly Available Date: Nov 13, 2023
• Journal: Astrophysical Journal
• Print ISSN: 0004-637X
• Electronic ISSN: 1538-4357
• Publisher: American Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 956
• Issue: 2
• Article Number: 104
• DOI: https://doi.org/10.3847/1538-4357/acf292
• Public URL: https://hull-repository.worktribe.com/output/4436399