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The PG X-Ray QSO Sample: Links among X-ray, UV & Optical Spectra

Beverley J. Wills·M. S. Brotherton·A. Laor·D. Wills·B. J. Wilkes·G. J. Ferland
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Abstract

A unique, essentially complete sample of 22 QSOs, with high quality soft X-ray spectra from ROSAT, as well as HST and optical spectrophotometry from below Ly-alpha to above H-alpha, is being used to investigate the relationships among the ionizing continuum and the optical and UV continuum, emission and absorption lines. Here we present a first analysis showing that optical `Eigenvector 1' linking steeper soft X-ray spectra with increasing optical Fe II strength, decreasing [O III] 5007 emission, and narrower BLR H-beta emission, extends to the UV emission lines, and is manifested by weaker C IV 1549 emission, stronger Si III] 1892/C III] 1909 ratio, and narrower C III] 1909 emission. Steeper soft X-ray spectra have been linked to higher L/L_Edd ratios, thus apparently linking BLR densities, high and low ionization gas, and kinematics, to the accretion process.

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Beverley J. Wills, M. S. Brotherton, A. Laor, D. Wills, B. J. Wilkes, G. J. Ferland. 1998-08-07. The PG X-Ray QSO Sample: Links among X-ray, UV & Optical Spectra. https://arxiv.org/abs/astro-ph/9808059

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