An Accreting Black Hole in the Nuclear Star Cluster of the Bulgeless Galaxy NGC 1042

TL;DR

This paper provides spectroscopic evidence for a low-luminosity intermediate-mass black hole in the nucleus of the bulgeless galaxy NGC 1042, coexisting with a star cluster, challenging traditional galaxy formation models.

Contribution

It presents the first evidence of a black hole in a bulgeless galaxy's nucleus, highlighting coexistence with a star cluster and implications for black hole formation theories.

Findings

Detection of a low-luminosity AGN in NGC 1042

Black hole coexists with a nuclear star cluster

Implications for black hole formation in bulgeless galaxies

Abstract

We present spectroscopic evidence for a low-luminosity, low-excitation active galactic nucleus (AGN) in NGC 1042, powered by an intermediate-mass black hole. These findings are significant in that the AGN is coincident with a compact star cluster known to reside in the nucleus, thus providing an example where the two types of central mass concentration coexist. The existence of a central black hole is additionally remarkable in that NGC 1042 lacks a stellar bulge. Objects such as NGC 1042 may have an important role in testing theories for the genesis of massive black holes in galaxy nuclei, and the extent to which they are in symbiosis with the larger stellar host.