AAS Meeting #193 - Austin, Texas, January 1999
Session 107. (Quasars and Blazars-) High Luminosity AGN and their Environments
Display, Saturday, January 9, 1999, 9:20am-4:00pm, Exhibit Hall 1

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[107.05] The PG X-ray QSO Sample: Ionizing Continuum and Properties of the Fueling Gas

B. J. Wills (Univ. Texas, Austin), A. Laor (Technion, Haifa), M. S. Brotherton (IGGP, LLNL), D. Wills, Zhaohui Shang (Univ. Texas, Austin), B. J. Wilkes (Harvard-Smithsonian CfA), G. J. Ferland (Univ. Kentucky)

The UV to soft X-rays of luminous AGNs dominate their bolometric luminosity, driven by an accretion-powered dynamo at the center. These photons illuminate the surrounding gas, providing clues to fueling and exhaust. Two sets of important relationships -- neither of them understood -- link the continuum and gas properties. These are the Baldwin relations between equivalent width and luminosity, and the so-called `Eigenvector 1' relationships linking steeper X-ray spectra with narrower BLR H\beta and stronger Fe\,II (optical), and weaker NLR [O\,III]\lambda5007 emission (Boroson & Green 1992, Laor et al. 1994, 1997). These relationships plausibly link the central engine with structure, dynamics and physical conditions in sub-parsec to Kiloparsec scale gas. In order to investigate these relationships further we study the links between optical and ultraviolet emission lines, and the UV and soft-X-ray ionizing continuum. We have obtained HST UV and McDonald ground-based spectra for a unique sample -- a complete sample of PG QSOs chosen for low redshift and low Galactic reddening by Laor et al. (1994) in order to obtain high-quality information on the ionizing continuum. We show that the above eigenvector 1 relationships extend to many properties of the UV spectrum.

We present examples of the new set of correlations, and speculate that a starburst origin for a component of QSO gas might explain its geometry, abundances and density. The link with dynamics and UV--X-ray SED suggests that this gas is fueling the accretion-driven central engine.

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