AGN Feedback Heating Kernels

Using hydrodynamic simulations of idealized galaxy clusters with Enzo, we investigated whether purely thermal AGN feedback models could replicate the cool-core clusters produced by kinetic jet AGN feedback models. Such a purely thermal feedback model would serve as a theoretical approximation of energy deposition by AGN jets. Although we found no such purely thermal heating kernel that maintained a cool-core cluster, we did develop a model between the radial deposition of energy by the AGN, the entropy profile of the cluster, and the stability of the cluster.

We identified three potential outcomes:

• Centrally underheating kernels, which lead to early cooling catastrophes.
• Centrally overheating kernels, which lead to unphysically elevated central entropies but ultimately stable clusters.
• Centrally intermediately heating kernels, which balance a reasonable central entropy These outcomes were borne out in the simulations depending on how centrally concentrated the AGN heating was.

Full explanations and descriptions are available in our paper in the Astrophysical Journal