Accurate AGN black hole masses and the scatter in the M_{bh} - L_{bulge} relationship

TL;DR

This paper presents a new empirical formula for estimating black hole masses in AGNs using H beta velocity dispersion and continuum luminosity, calibrated to existing methods, revealing minimal scatter in high-luminosity galaxies and increased scatter in lower-mass ones.

Contribution

The paper introduces a novel empirical formula for black hole mass estimation in AGNs, calibrated to reverberation-mapping and stellar-dynamical data, improving accuracy and understanding of the M_{bh} - L_{bulge} relationship.

Findings

Mass estimates are as accurate as existing methods.

Minimal scatter in the M_{bh} - L_{bulge} relation for high-luminosity galaxies.

Scatter increases significantly in lower-mass galaxies.

Abstract

A new empirical formulae is given for estimating the masses of black holes in AGNs from the H beta velocity dispersion and the continuum luminosity at 5100 Angstroms. It is calibrated to reverberation-mapping and stellar-dynamical estimates of black hole masses. The resulting mass estimates are as accurate as reverberation-mapping and stellar-dynamical estimates. The new mass estimates show that there is very little scatter in the M_{bh} - L_{bulge} relationship for high-luminosity galaxies, and that the scatter increases substantially in lower-mass galaxies.