Probing the Invisible: Weighing Supermassive Black Holes
Martin Bureau
Oxford University

Supermassive black holes are now known to lurk at the centres of most galaxies, and are believed to play a key role in their evolution. Here, I will present key results from the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM), a high resolution survey of molecular gas in galaxy nuclei. First, I will show that CO can be used to easily and accurately measure the masses of the supermassive black holes lurking at galaxy centres. Second, I will discuss substantial ongoing efforts to do exactly that, and present many spectacular new measurements, the latest of which rival the best black hole measurements to date. Third, I will compare molecular gas and megamaser measurements, discuss black hole scaling relations, and introduce the newly-discovered mm fundamental plane of black hole accretion, that is surprisingly tight and holds for a wide variety of active galactic nuclei and stellar-mass black holes. This work opens the way to literally hundreds of measurements across the Hubble sequence (in both active and non-active galaxies) with a unique method, and thus promises to revolutionise our understanding of the co-evolution of galaxies and black holes.

Date:	Tuesday, 19 September 2023
Time:	15:30
Where:	McGill University
	Bell Room (Rutherford 103)