Collaborative Research: Exploring Star Formation in the Early Universe through Investigations of High-Redshift ISM

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AST-0708543/0709235Wolfe/ProchaskaThis collaboration, led by Dr. A.Wolfe, will examine the relationship between neutral gas and young stars at high redshift, by applying diagnostic tools developed for the local interstellar medium (ISM). Most of what we know about star formation in high-redshift galaxies stems from observing them in emission, but damped Lyman-alpha systems (DLAs) are detected in absorption against quasars. In general, these galaxies are more representative than any other high-redshift objects detected in emission. This study will (1) discover and analyze over 1000 new DLAs, identifying a large sample of galaxies for ISM research, (2) triple the number of DLAs with detected carbon-II absorption in the ultraviolet, to measure the gas cooling and heating rates, (3) pursue preliminary observations of carbon-II emission in the sub-millimeter wavelength range, coming from the cold neutral gas in DLAs, to determine the sizes and masses of high-redshift galaxies, (4) search for Hydrogen-alpha emission from DLAs, mapping the velocity field of the ionized gas for evidence of galaxy rotation, (5) measure the temperature, density, molecular content and multi-phase structure of the ISM in young galaxies, and finally, (6) measure magnetic fields in intermediate-redshift DLAs by detecting Zeeman splitting in the 21-cm absorption lines using the Green Bank Telescope.The impact of DLA science has steadily grown beyond the field of quasar absorption lines, to include chemical evolution and nucleosynthesis in the early Universe, variations in the fine-structure constant; and global constraints on critical aspects of galaxy formation. The present research will therefore be widely disseminated to the astronomical population, and beyond to the general education community through an advanced Web site. In addition, support for graduate students and exposing undergraduates to cutting-edge research are staple activities of these researchers.