TAPIR Seminar

Stellar feedback is an indispensable component in galaxy evolution, which regulates star formation, drive galactic winds, and shape the galaxy structures. With the "Feedback in Realistic Environment" (FIRE) simulations, I demonstrate the importance of stellar feedback with a few examples: 1. how stellar feedback modifies the underlying dark matter halo structures, 2. how stellar feedback produces diffuse dwarf galaxies, e.g. ultra diffuse galaxies. In the second part of my talk, I will focus on an important kind of stellar feedback — cosmic ray (CR) feedback, which we have recently implemented in the code GIZMO and coupled to the FIRE stellar feedback model. I will demonstrate its strong effects on galaxies, e.g. star formation, galactic wind, and circum-galactic medium, but the effects highly depend on the CR propagation model. I will then show how to constrain those models by comparing our simulations with the observed gamma ray emission. Finally, I will discuss the ongoing research and future directions on CR feedback.