Neutral atomic hydrogen (HI) is a critical ingredient in galaxy evolution because it serves as an intermediate phase between the warm-hot intergalactic medium and the cold molecular gas that forms stars in galaxies. In galaxy groups, systems of galaxies occupying common dark matter halos, many group processes such as merging and stripping affect the HI reservoirs of galaxies, thereby changing their capacity for future star formation. As part of my dissertation research, I am using the REsolved Spectroscopy Of a Local VolumE (RESOLVE) and Environmental COntext (ECO) surveys to probe atomic hydrogen in galaxy groups in the local Universe, both inside and outside galaxies, and the relationship of group HI to group halo mass, local environmental density, and group evolutionary state. I further describe work in progress that will combine RESOLVE and ECO with archival X-ray data to directly examine how hot intragroup gas impacts group HI content and to investigate the apparent connection between halo gas heating and group formation. Finally, I describe how RESOLVE and ECO can be compared with LADUMA (Looking At the Distant Universe with the MeerKAT Array), the first survey to probe HI in emission in the cosmic past (out to z~1.4). By comparing RESOLVE, ECO, and LADUMA, we can directly measure cosmic evolution in the atomic hydrogen content of galaxy groups over the last ~5 billion years.

Speaker: Zack Hutchens

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https://unc.zoom.us/j/96704729718