Dissecting The Gaseous Halos Of Massive Quiescent Galaxies (speaker: Fakhri Zahedy, University Of Chicago)

Monday November 19, 2018 12:05 pm
Marlar Lounge 37-252

Significant progress has been made in understanding the many aspects of galaxy evolution over the past two decades. However, what still eludes us is a self-consistent explanation of the diffuse gas surrounding galaxies, known as the circumgalactic medium (CGM). Particularly puzzling is the widespread presence of cool (10^4 K) gas in the CGM of massive quiescent galaxies, contrary to expectation that the gas is hot (>10^6 K). A systematic characterization of the gaseous halos of massive “red and dead” galaxies is necessary to solve this puzzle. I will highlight the latest findings from our observational efforts studying diffuse gas around distant massive quiescent galaxies using the Hubble Space Telescope and large ground-based telescopes. I will illustrate what investigating the elemental abundance and abundance patterns, kinematics, and ionization states of the gas tells us about the nature of physical processes in the CGM of massive quiescent galaxies. I will discuss the implications of these findings on the origin and fate of the gas, and point to a future direction for our quest to understand the co-