Astro Seminar
Precise diagnostics of AGN-driven outflows
Speaker: Luke Holden (University of Sheffield)
Date: Wednesday 7 February 2024
Time: 14:00
Venue: N3.28/Zoom
In order to explain the observed properties of the local galaxy population, theoretical models of galaxy evolution now routinely require that accreting black holes in galactic centres (active galactic nuclei, or AGN) accelerate powerful, galaxy-wide outflows of gas. These AGN-driven outflows are thought to heat and expel gas needed for star formation, significantly impacting how galaxies evolve. However, despite much progress in understanding the properties and natures of AGN-driven outflows over the past two decades, their true roles in galaxy evolution remain unclear. Principally, this is because there are many uncertainties involved in deriving outflow properties from observations. To address this, we have undertaken a series of detailed, single-object studies of nearby AGN that have developed and used robust diagnostics of outflowing gas. In this talk, I will review the results of our studies, which highlight the careful considerations that are required to determine the true impact of outflows on host galaxies. Overall, I argue that detailed, multi-wavelength observations and precise diagnostics are needed to robustly assess the role of AGN-driven outflows in galaxy evolution.