Mass Functions of Supermassive Black Holes Across Cosmic Time

TL;DR

This review discusses methods for estimating the supermassive black hole mass function, compares empirical results with theoretical models, and highlights future research directions to improve understanding of black hole growth over cosmic time.

Contribution

It provides a comprehensive overview of current methods, results, and models for the supermassive black hole mass function, and suggests future research pathways.

Findings

Comparison of active and inactive black hole mass functions

Evaluation of methods for estimating the mass function

Discussion of theoretical models and future directions

Abstract

The black hole mass function of supermassive black holes describes the evolution of the distribution of black hole mass. It is one of the primary empirical tools available for mapping the growth of supermassive black holes and for constraining theoretical models of their evolution. In this review we discuss methods for estimating the black hole mass function, including their advantages and disadvantages. We also review the results of using these methods for estimating the mass function of both active and inactive black holes. In addition, we review current theoretical models for the growth of supermassive black holes that predict the black hole mass function. We conclude with a discussion of directions for future research which will lead to improvement in both empirical and theoretical determinations of the mass function of supermassive black holes.