Galaxy groups as the ultimate probe of AGN feedback
Dominique Eckert (Invited)
The co-evolution between supermassive black holes and their environment is most directly traced by the hot atmospheres of dark matter halos. Cooling of the hot atmosphere supplies the central regions with fresh gas, igniting AGN with long duty cycles. Outflows from the central engine tightly couple with the surrounding gaseous medium and provide the dominant heating source preventing runaway cooling. Every major modern hydrodynamical simulation suite now includes a prescription for AGN feedback to reproduce realistic populations of galaxies. Galaxy groups are uniquely suited to constrain the mechanisms governing the cooling-heating balance, as the energy supplied by the central AGN can exceed the gravitational binding energy of halo gas particles. I will review our knowledge of the impact of AGN on the hot atmospheres of galaxy groups, with a specific focus on the thermodynamic profiles of groups. I will then present our on-going efforts to improve on the implementation of AGN feedback in galaxy evolution models by providing precise benchmarks on the properties of galaxy groups. Finally, I will describe how new instrumentation (in particular Athena) will answer key open questions on the topic.