Massive Black Holes Across the Mass Spectrum

Overview

Known massive black holes span roughly eight decades in mass, but the census is far from uniform. The interval between about 10² and 10⁵ M_☉ — the intermediate-mass black holes — remains almost empty, not necessarily because such objects are rare but because their gravitational sphere of influence subtends only a few tens of milliarcseconds even in the nearest dwarf galaxies, nuclear star clusters and globular clusters. At the opposite extreme, the most massive black holes in brightest cluster galaxies probe the limits of accretion and merger-driven growth. Because different mass ranges are traditionally studied with different techniques — stellar dynamics, cold-gas dynamics, reverberation mapping, single-epoch AGN scaling — systematic offsets between methods can easily masquerade as physical structure in the mass function. Applying one carefully controlled dynamical framework across the full spectrum is therefore essential.

My Research

I am developing a Python pipeline that separates the AGN continuum from the underlying stellar light in JWST/NIRSpec and NIRCam data, which is the key step for extracting uncontaminated stellar kinematics in active nuclei, and I lead supermassive black hole mass measurements in NGC 4258 and M87. In parallel I model ALMA datacubes with KinMS to determine black hole masses in NGC 7052, NGC 4061, NGC 2513 and Circinus. On the intermediate-mass side, I simulate mock HARMONI integral-field datacubes and MICADO imaging of dwarf galaxies, nuclear star clusters and globular clusters, recover the input masses through dynamical modelling, and map out where the ELT will and will not be able to detect intermediate-mass black holes within about 20 Mpc.

Literature Review

Summary of Findings