Astro Lunch: Zach Hafen (UC Irvine)

February 26, 2021 - 12:00pm


 From Observations to Origins and Fates: Disentangling Gas Flows Around Galaxies

 As much as half of the gas mass in our Galaxy’s dark matter halo may reside not in the galaxy itself, but at the interface between our Galaxy and the cosmic web, the circumgalactic medium (CGM). The vast gas content of the CGM, loosely defined as the volume immediately outside the galaxy but inside the dark matter halo, is crucially involved in galaxy formation: accretion from the CGM onto the central galaxy provides the material necessary to fuel observed star formation rates, while galactic winds ejected into the CGM are are primarily responsible for regulating star formation in galaxies below the mass of the Milky Way and polluting the intergalactic medium. Despite their individual importance, determining the exact roles of circumgalactic accretion/winds and differentiating them in observations is an outstanding problem in galaxy formation. I will cover recent work aimed at disentangling these gas flows using hydrodynamic galaxy formation simulations, both in the observer-centric frame of mock absorption observations and in the theorist-centric frame of the worldlines of individual clouds of gas.


Location and Address

Zoom ID: 970 3971 4442

Department members, see email for access.
Non-department members, contact foraccess or to be added to the weekly newsletter.