Speaker: Dr. Hsiang-Yi Yang (University of Maryland, USA)

Time:      10:30 am, Feb 17, 2017 (Fri)

Venue:    R620, Physics Building

Title: The Microphysics of AGN Feedback

Feedback from active galactic nuclei (AGN) is one of the most important processes governing the formation and evolution of galaxies and galaxy clusters. It is believed to be responsible for inhibiting the formation of massive galaxies and for solving the long-standing cooling-flow problem in galaxy clusters. 

A lot of understanding of AGN feedback has been gained using hydrodynamic simulations; however, some of the relevant physical processes are unresolvable or not captured by pure hydrodynamics, such as plasma effects and cosmic-ray (CR) physics.

In this talk, I will present how we use simulations that incorporate this microphysics to understand how AGN jets feedback on galactic and cluster scales. Specifically, I will discuss the roles of thermal conduction and CRs in addition to purely hydrodynamic models. I will also talk about how we could use multi-messenger observations of the Fermi bubbles as a nearby laboratory for studying AGN feedback. Finally, I will conclude with open questions and future prospects of applying simulations beyond hydrodynamics to various interesting astrophysical systems.