Baitian Tang, Zhaohui Shang, Qiusheng Gu, Michael S. Brotherton, Jessie C. Runnoe
We present measurements and statistical properties of the optical and ultraviolet emission lines present in the spectra of 85 bright quasars which have detailed spectral energy distributions. This heterogeneous sample has redshifts up to z=1.5 and is comprised of three subsamples that may be of particular utility: ultraviolet excess Palomar-Green quasars, quasars with far-ultraviolet coverage from FUSE, and radio-loud quasars selected to have similar extended radio luminosity originally selected for orientation studies. Most of the objects have quasi-simultaneous optical-ultraviolet spectra, with significant coverage in the radio-to-X-ray wavebands. The parameters of all strong emission lines are measured by detailed spectral fitting. Many significant correlations previously found among quasar emission-line properties are also present in this sample, e.g., the Baldwin effect, the optical correlations collectively known as eigenvector 1, and others. Finally, we use our measurements plus scaling relationships to estimate black hole masses and Eddington fractions. We show the mass estimates from different emission lines are usually in agreement within a factor of 2, but nearly a third show larger differences. We suggest using multiple mass scaling relationships to estimate black hole masses when possible, and adopting a median of the estimates as the black hole mass for individual objects. Line measurements and derived AGN properties will be used for future studies examining the relationships among quasar emission lines and their spectral energy distributions.
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http://arxiv.org/abs/1207.2539
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