Radio-loud active galactic nuclei in the context of the eigenvector 1 parameter space

We consider the properties of radio-loud (RL) active galactic nuclei in the context of the eigenvector 1 (E1) parameter space. RL sources show a restricted E1 parameter space occupation relative to the radio-quiet (RQ) majority. The Fanaroff-Riley II parent population of relatively unboosted RL sources (median radio/optical flux ratio similar to490) shows the most restricted occupation. RL sources have different broad-line properties (and inferred black hole masses and Eddington ratios). FWHM Hbeta for the broad-line component in RL sources are at least twice as large as in the RQ majority. The average broad Fe II lambda4570 emission-line strength is also about half that for RQ sources. Our sample suggests that the RL cutoff occurs near R-K approximate to 70 or log P-6 cm similar to ergs s(-1) Hz(-1). Sources below this cutoff are RQ, although we cannot rule out the existence of a distinct intermediate population. We show that the Doppler-boosted core-dominated RL sources (median flux ratio similar to1000) lie toward smaller FWHM(Hbeta(BC)) and stronger Fe IIopt in E1, as expected if the lines arise in an accretion disk. Our subsample of superluminal sources, with orientation inferred from the synchrotron self-Compton model, reinforce this general E1 trend and allow us to estimate the role of source orientation in driving E1 domain occupation.