Quasi-Stellar Object (QSO) Investigations of the Universe at Large Redshifts

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High redshift quasars will be used to study the distribution and state of matter at early epochs of the universe. The radiation from quasars passes through the gas in intervening galaxies. The gas in the galaxies can be studied by studying the absorption lines of the quasar spectrum. Observations at radio and optical wavelengths and theoretical analysis and simulations will be made to improve our understanding of the stages of galaxy evolution at redshifts from 1.8 to 4. The study will include both the detailed investigation of particular objects that have been identified to be of special interest and new survey work to answer statistical questions as well as providing new objects for follow-up work. The principle goal is completion of a study of a population of Quasi-Stellar Object (QSO) absorption systems that are characterized by heavily damped Lyman alpha hydrogen lines, they appear to be the progenitors of galactic disks. A search will be made for radiation emitted by stars that are presumably responsible for the production of heavy elements. The stars emit ionizing radiation which is converted to Lyman alpha by the neutral hydrogen (HI) layer. Thus, the ionizing flux is concentrated in the Lyman alpha line which subsequently escapes and may be detected in the spectrum. Surveys for dust in the damped systems, hydrodynamic simulations of the collapse to "HI disks", and further radio investigations of both nearby disk galaxies and redshifted 21 cm wavelength hydrogen line absorption systems will be carried out.