April 22
Regulating the Growth of Galaxies Through their Atmospheres
Speaker: Dr. Chris Carr, Princeton University
Abstract: The circumgalactic medium (CGM) is a vast, multiphase atmosphere of gas bound to galaxy halos, situated at the intersection of inflows from the cosmic web, swarming satellites, and outflows from central galaxies. Precisely how these diverse processes interact to shape the thermodynamics of the CGM and the distribution of its baryons—and, in turn, how the CGM regulates the baryon cycle—remains a key challenge in uncovering the drivers of galaxy growth. In this talk, I will first present a simplified, one-dimensional analytic model of the CGM–galaxy connection, to investigate the key processes governing star formation in galaxies and their impact on the mass, energy, and metal contents of their surrounding galactic atmospheres. I will show how this model self-consistently couples mass and energy outflow rates from galactic winds to the large-scale heating and cooling of the CGM, thereby self-regulating the growth of galaxies in a way consistent with fundamental galaxy scaling relations. Lastly, I will discuss ongoing efforts to extend this framework to the coupled chemical evolution of galaxies and their CGM and conclude with future research directions exploring how CGM energetics interact with feedback in galaxy groups and clusters to redistribute baryons on cosmic scales.
Host: Ankita Bera