Kinematics of the Circumgalactic Gas: How Do Galaxies Get Their Gas
Stephanie Ho (Texas A&M)
October 27 @ 12:00 PM - 1:00 PM
Galactic disks grow by accreting cooling gas from the circumgalactic medium (CGM). Although decades of observations have demonstrated that galaxies need a continuous gas supply to explain the star formation history, direct observations of gas accretion onto galaxies remain sparse. We will present results from our survey of using background quasar sightlines to measure the kinematics of the cool (~10^4 K) CGM of low-redshift, star-forming galaxies. In particular, we will show that although the inner CGM corotates with the galactic disk, the centrifugal force only partially supports the circumgalactic gas, implying that the angular momentum of the CGM delays accretion onto the disk. We will also present our analysis with the EAGLE cosmological simulation and focus on the circumgalactic gas kinematics. Our study with EAGLE will provide insight into interpreting our circumgalactic kinematic observations and understanding how gas feeds the galactic disks.
Please contact the department office for Zoom information.