Low-Mass AGN and Their Relation to the Fundamental Plane of Black Hole Accretion

TL;DR

This study demonstrates that low-mass active galactic nuclei (AGNs) follow the same fundamental plane of black hole accretion as stellar-mass black holes, supporting its universality across different black hole mass ranges.

Contribution

The paper provides observational evidence that low-mass AGNs conform to the fundamental plane, extending its applicability to black holes with masses below 10^7 solar masses.

Findings

Low-mass AGNs lie on the same fundamental plane as stellar-mass black holes.

The fundamental plane can be used to estimate masses of low-mass and intermediate-mass black holes.

Results support the universality of black hole accretion processes across mass scales.

Abstract

We put active galactic nuclei (AGNs) with low-mass black holes on the fundamental plane of black hole accretion---the plane that relates X-ray emission, radio emission, and mass of an accreting black hole---to test whether or not the relation is universal for both stellar-mass and supermassive black holes. We use new Chandra X-ray and Very Large Array radio observations of a sample of black holes with masses less than $10^{6.3}\ M_{\scriptscriptstyle \odot}$, which have the best leverage for determining whether supermassive black holes and stellar-mass black holes belong on the same plane. Our results suggest that the two different classes of black holes both belong on the same relation. These results allow us to conclude that the fundamental plane is suitable for use in estimating supermassive black hole masses smaller than $\sim 10^7\ M_{\scriptscriptstyle \odot}$, in testing for intermediate-mass black holes, and in estimating masses at high accretion rates.