RUI/AAG - Studying Metals in Quasars From the Sloan Digital sky Survey: Observing Changes in Galaxy Properties Over Time via Absorption Spectra

University Of Hawaii At Hilo, Hilo HI

Investigators

Abstract

Part 1 The proposed research aims to connect gas clouds and gaseous structures with galaxies and their change over time. The observations of elements heavier than helium in these gas clouds provides important constraints on the overall amount of these elements produced and spread through space, and the physical environments of gas clouds themselves. The proposal seeks to study a large sample of quasars from an important sky survey, using the quasars like a flash light to observe gas clouds (and their properties) between us and the more distant quasars. Part 2 The large-scale gaseous structure of the Universe is affected by the production and dispersal of chemical elements by galactic processes. Quasar absorption-line (QAL) spectroscopy is a powerful tool for probing the large-scale gaseous structure and its change over time. There is an emerging consensus that strong absorption-line systems trace the extended gaseous halos of galaxies. The evidence relies on direct detections of strong absorbers near galaxies as well as absorber properties changing with galaxies. The large scale of this enriched circum-galactic medium (CGM) enables the study of galaxy formation and change with relatively little observational expense, at a wide range of redshifts. Open questions in astronomy motivate the research: What are the chemical properties of the extended gaseous halos of galaxies? Which type of absorption-line systems are associated with what class of galaxies? Where are the missing metals? Toward what galaxies are potential cold flows flowing?