0 Assigned ID: 1882 ----- Attempting Submission 1 (Fri Apr 09 11:48:58 GMT 2021) ----- HST Phase I Proposal 1882 successfully submitted. Receipt: # 1882-1 ----- Attempting Submission 2 (Fri Apr 09 13:07:03 GMT 2021) ----- Cosmological hydrodynamic simulations predict galaxy mass assembly via infall from the circum- and inter- galactic medium. Infall can also occur via large scale circulations, or in association with satellite galaxies. While outflows and feedback from starbursts and quasars are extensively studied, little is known about infall, e.g. during active stages of galaxy evolution that can overlap with quasar activity. Quasar absorption lines provide unique probes of the physical properties of gas inflows and outflows in quasar host galaxies. We propose an absorption line study of inflows in 600 quasars at 0.1 < z < 1.4 using their high resolution HST spectra. The redshift range will probe a poorly understood cosmic epoch after the heyday of massive galaxy formation. It will also place diagnostic UV absorption lines within HST wavelength coverage, avoid severe contamination by Lya forest at higher redshifts, and allow obtaining accurate systemic redshifts via emission lines in existing ground spectra. The absorption lines covered range from CIV 1549,1550, CII 1334,1335* to OVI1031,1037, NeVIII770,780, and OIV608,609*, and will provide critical constraints on absorber kinematics, ionization levels, column densities, chemical abundances, and in some cases densities and locations. Abundance constraints are particularly important to distinguish between primordial infall and fountains already enriched inside galaxies. We will also compare the incidence and physical properties of the inflows to the more commonly measured outflows. Our goals are to understand the nature and origins of the infall systems, including their relationships to outflows, quasar feedback, and galaxy assembly. PI Lau has extensive experience in analyzing the diverse gaseous environments of a diversity of quasars. The PI has the skills to study the gas in absorption and in emission, and in spectroscopy and imaging. Co-Is Hamann, Perrotta, and Tripp are experts in studying quasar associated absorbers. They are involved in some pioneering papers on high redshift quasar associated gas flows in absorption and emission, and in calibrating HST and ground spectra for a range of absorber natures and properties. Supermassive Black Holes and Active Galaxies Intergalactic Medium and the Circumgalactic Medium 0 Regular false false true false false SUPPORTED