Speaker:	Chris Done (University of Durham)
Title:	Unifying black hole accretion flows, their winds and jets across the mass scale.
Date (JST):	Wed, Jan 21, 2026, 15:30 - 17:00
Place:	Lecture Hall
Abstract:	The co-evolution of black holes and their host galaxies points to a deep connection between them, most probably via feedback of the accretion power in Active Galactic Nuclei (AGN) via winds and the jet. Yet these components are not well understood. I will describe recent breakthroughs in understanding winds that come from new data from the XRISM satellite, and show how the most powerful winds can be launched by radiation pressure. This means that they change with the spectrum and luminosity of the accretion flow. I will outline recent progress in understanding these, in particular the existence of an abrupt transition in the nature of the accretion flow at low luminosities, to a radiatively inefficient X-ray hot flow. This occurs across the AGN population but is most clearly seen in individual ”®changing look”Æ events which I will illustrate with new data. I will show the behavior of the radio jet across this transition, and how this supports models where the jet power is a constant fraction of the accretion power in the X-ray hot plasma (the 'Fundamental Plane') but AGN also can show very rare 'radio loud’ jets, where black holes with the same mass and mass accretion rates have radio fluxes which are 3 orders of magnitude brighter than the majority radio-quiet population. I will show a new model for the accretion structure, and its jet, which can encompass all these properties, and describe how it can be tested with new data.

← Back