24–28 Aug 2026
Leiden University
Europe/Zurich timezone

Dark Matter and Stellar Dynamics Around Massive Black Holes

Not scheduled
20m
Gorlaeus gebouw (Leiden University)

Gorlaeus gebouw

Leiden University

Einsteinweg 55, 2333 CC Leiden
Talk Gravitational Waves

Speaker

Barry Ginat (University of Oxford)

Description

In this talk, I will describe how to use stellar dynamics to constrain the distribution of dark matter around super-massive black holes, in two cases. First, concerning gravitational atoms of fuzzy dark matter (FDM) around black holes with nuclear stellar discs (like the Milky Way's): I will show that if the atom is in a spherically asymmetric state, there will be a differential torque on the disc that could disrupt it; any observations of the existence and stability of this disc can thus be used to put constraints on the FDM particle mass. Moving on to cold dark matter, I will describe how the interaction of a "dark matter spike" (a strong density cusp that can exist around black holes) with the stellar population in the nuclear cluster can lead to markedly different behaviour and density profiles, to the extent that most of the spike is sometimes evaporated. For both cases, I will describe which black-hole masses (and other parameter values) are most sensitive to these effects.

Other topic / keywords: Super-massive black holes

Authors

Barry Ginat (University of Oxford) Mr Charlie Sharpe (University of Oxford)

Co-authors

Prof. Bence Kocsis (University of Oxford) Dr Thomas Spieksma (University of Oxford)

Presentation materials

There are no materials yet.