Abstract:
Galaxy growth is a slow but continuous process. The observed properties of galaxies suggest that accretion must continue to support star formation. However, direct observational evidence of gas flows into galaxies have been extremely hard to come by. One of the most promising regions in our search has been the disk-halo interface, where new data are uncovering signs of gas condensation. In this talk, I will discuss the results from our ongoing DIISC (Deciphering the Interplay between the ISM, Stars, and the CGM) survey, which probes the disk-CGM interface with QSO sightlines. I’ll discuss our findings in terms of the signpost of gas accretion and galactic feedback and show evidence that structures such as high-velocity clouds and extra-planar gas that are seen in the Milky Way and a few other galaxies are indeed prevalent in most galaxies. These gaseous structures represent a pathway for gas accretion into galaxies and can be one of the primary ways how galaxy disks grow in the nearby Universe.
Host: Rob Simcoe
Photo credit for the galaxy picture: Shireen Dooling/ASU