| Description: | Accretion of matter by supermassive black holes residing at the centres of galaxies is responsible for triggering Active Galactic Nuclei (AGNs), the most energetic objects in the Universe. Observational and theoretical evidence collected in recent years strongly suggests that these objects play a crucial role in galaxy formation and evolution. They do this via the process of AGN feedback, where a fraction of the AGN energy output couples to the surrounding gas. While there are many ways in which AGN can do feedback, the so-called "radio-mode" has been dominant since z ~ 1. In this scenario, AGN feedback from radio jets regulates gas cooling, and has been invoked to explain the lack of a cooling catastrophe in galaxy clusters, and the dearth of widespread star formation in massive galaxies at low redshift.
While we understand the consequences of AGN feedback reasonably well, teasing out the physical mechanisms driving the feedback has proved tricky. In particular, quantifying the efficiency of AGN feedback is difficult. A promising way forward is to combine dynamical models of radio AGN with semi-analytic galaxy formation models. I will describe these two techniques, and explain how they can be used together to (i) interpret AGN observables; and (ii) study the mechanisms responsible for AGN triggering and feedback. |
