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2011AJ....141..182K Correlations of Quasar Optical Spectra with Radio Morphology Kimball, Amy E.; Ivezic, Zeljko; Wiita, Paul J.; Schneider, Donald P. Abstract. Using the largest homogeneous quasar sample with high-quality optical spectra and robust radio morphology classifications assembled to date, we investigate relationships between radio and optical properties with unprecedented statistical power. The sample consists of 4714 radio quasars from FIRST with S_20_ >= 2 mJy and with spectra from the Sloan Digital Sky Survey (SDSS). Radio morphology classes include core-only (core), core-lobe (lobe), core-jet (jet), lobe-core-lobe (triple), and double-lobe. Electronic tables of the quasar samples, along with spectral composites for individual morphology classes, are made available. We examine the optical colors of these subsamples and find that radio quasars with core emission unresolved by FIRST (on ~5" scale) have a redder color distribution than radio-quiet quasars (S_20_ <~ 1 mJy); other classes of radio quasars have optical color distributions similar to the radio-quiet quasars. This analysis also suggests that optical colors of z <~ 2.7 SDSS quasars are not strongly (<0.1 mag) biased blue. We show that the radio core-to-lobe flux density ratio (R) and the radio-to-optical (i-band) ratio of the quasar core (R_I_) are correlated, which supports the hypothesis that both parameters are indicative of line-of-sight orientation. We investigate spectral line equivalent widths (EWs) as a function of R and R_I_, including the O [III] narrow line doublet and the C IV {lambda}1549 and Mg II {lambda}2799 broad lines. We find that the rest EWs of the broad lines correlate positively with R_I_ at the 4{sigma}-8{sigma} level. However, we find no strong dependence of EW on R, in contrast to previously published results. A possible interpretation of these results is that EWs of quasar emission lines increase as the line-of-sight angle to the radio-jet axis decreases. These results are in stark contrast to commonly accepted orientation-based theories, which suggest that continuum emission should increase as the angle to the radio-jet axis decreases, resulting in smaller EWs of emission lines (assumed isotropic). Finally, we observe the Baldwin effect in our sample and find that it does not depend strongly on quasar radio morphology. Key words: quasars: emission lines, quasars: general =========================================================================== 2011AJ....142..143K ERRATUM: "Correlations of Quasar Optical Spectra with Radio Morphology" (2011, AJ, 141, 182) Kimball, Amy E.; Ivezic, Zeljko; Wiita, Paul J.; Schneider, Donald P. Abstract. Equation (3) in the published article contained a sign error, such that the two terms in the exponent were reversed. The correct version of the equation is {see text}. This correction only affects the published equation. The code that calculated the R values for the plots and analysis in the published article used the correct formula. A separate error led to incorrect values in three rows of Table 8. Owing to an error in the software, the linear regression analysis was performed using the wrong abscissa values for the three rows corresponding to the lobe morphology class for equivalent width versus R. We provide the corrected table in its entirety below. None of the corrected linear regressions suggests a significant correlation; thus there is no change to the overall conclusions presented in the published article. This correction also affects the middle panels of Figures 12-14, which show the best-fit line for these sources. The figures are reproduced below with the corrected best-fit lines. {see Figures 12, 13, 14 and Table 8} We are grateful to Dr. Neal Jackson for bringing these errors to our attention. ===========================================================================
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