A New Subgrid Model for AGN Feedback in Galaxy Clusters

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

Most galaxies have supermassive black holes in their centers. As these black holes swallow gas, they produce jets that can remove gas in a process known as feedback. Many galaxies inhabit clusters of galaxies and feedback can influence both the growth of the galaxies and the evolution of galaxy clusters. This project will develop and refine a method for simulating the effect of gas accretion on feedback. This method can be used to better model the growth of galaxies and galaxy clusters over cosmic time. The project will also develop web-based demonstrations of cosmology for use in classrooms. It will also support a girls' science summer camp for high school girls. The project will complete the development of a novel sub grid mode for active galactic nucleus (AGN) feedback in clusters of galaxies. The model treats the central black hole as a sink particle and computes the accretion rate using integration over a resolved control surface. The accretion rate is then used to determine the state of an accretion disk model which will determine the form and efficiency of the feedback. The model will be applied to 3D adaptive mesh refinement simulations of the centers of clusters of galaxies to investigate two questions: how accretion disk state transitions interact with large-scale flows in cluster cores; and how binarity resulting from mergers of the brightest cluster galaxies affects AGN feedback. An existing web site for computational astrophysics education will be upgraded with new simulations tools, and an existing outreach camp program will be improved with resources for additional activity days and projects. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.