Triggering and delivery methods for AGN feedback

Abstract

In this talk I present a comparison of several common sub-grid implementations of AGN feedback, focusing on the effects of different triggering mechanisms and the differences between thermal and kinetic feedback (although we also attempt to assess the importance of physical resolution and some AGN jet properties as well). Our main result is that pure thermal feedback that is centrally injected behaves differently from feedback with even a small kinetic component. We do not see large differences between implementations of different triggering mechanisms, as long as the spatial resolution is sufficiently high, probably because all of the implementations tested here trigger strong AGN feedback under similar conditions. Our simulations confirm that AGN can regulate the thermal state of cool-core galaxy clusters and maintain the core in a state that is marginally susceptible to thermal instability and precipitation.