Collaborative research: Exploring the impact of cosmic ray feedback on galaxy evolution

University Of Chicago, Chicago IL

Investigators

Abstract

Astronomers seek to understand how galaxies formed and evolve. Vast filaments of matter coalesce into galaxies under gravity. However, unknown forces from within expel gas in the form of galactic winds. Ruszkowski and collaborators seek to understand whether this missing force could be provided by cosmic rays. Using computer simulations, they will study effects of cosmic rays on galactic winds. They will determine whether cosmic rays contribute sufficient force to these winds to expel matter from galaxies completely. Finally understanding what powers galactic winds will contribute a major advance. This study may enable a qualitative leap in our understanding of how galaxies evolve. Results of these simulations will be used in stunning planetarium animations. Such visualizations engage the public and inspire young people to study science. This study will probe a range of spatial scales. It will include hybrid kinetic simulations of cosmic ray propagation around isolated supernova remnants out to galactic disks and finally to cosmological galaxy formation. Cosmic-ray transport physics will be simulated from first principles. Local patches of the interstellar medium will be simulated using adaptive mesh refinement. These results in turn will be used to develop sub-grid models for galaxy and cosmological formation simulations. This project will constitute the first large-scale study of galaxy formation to include cosmic-ray transport processes on all spatial scales. It will yield specific predictions for the properties of cosmic-ray driven galactic winds.