[Oii] Emission, Eigenvector 1, and Orientation in Radio‐quiet Quasars

We present supportive evidence that the Boroson and Green eigenvector 1 isnot driven by source orientation. Until recently it was generally accepted thateigenvector 1 does not depend on orientation as it strongly correlates with[OIII]5007 emission, thought to be an isotropic property. However, recentstudies of radio-loud AGN have questioned the isotropy of [OIII] emission andconcluded that [OII]3727 emission is isotropic. In this paper we investigatethe relation between eigenvector 1 and [OII] emission in radio-quiet BQS(Bright Quasar Survey) quasars, and readdress the issue of orientation as thedriver of eigenvector 1. We find significant correlations between eigenvector 1and orientation independent [OII] emission, which implies that orientation doesnot drive eigenvector 1. The luminosities and equivalent widths of [OIII] and[OII] correlate with one another, and the range in luminosities and equivalentwidths is similar. This suggests that the radio-quiet BQS quasars are largelyfree of orientation dependent dust effects and ionization dependent effects inthe narrow-line region. We also conclude that neither the [OIII] emission northe [OII]/[OIII] ratio are dependent on orientation in our radio-quiet BQSquasar sample, contrary to recent results found for radio-loud quasars.Comment: 24 pages, 12 figures, accepted for publication in Ap