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

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 Lyα to above Hα, 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 Xray spectra with increasing optical Fe II strength, decreasing [O III]λ5007 emission, and narrower BLR Hβ emission, extends to the UV emission lines, and is manifested by weaker C IVλ1549 emission, stronger Si III]λ1892/C III]λ1909 ratio, and narrower C III]λ1909 emission. Steeper soft X-ray spectra have been linked to higher L/LEdd ratios, thus apparently linking BLR densities, high and low ionization gas, and kinematics, to the accretion process.