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تسجيل مستخدم جديدWhat does Civ{lambda}1549 tell us about the physical driver of the Eigenvector Quasar Sequence?
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Broad emission lines in quasars enable us to resolve structure and kinematics of the broad line emitting region (BLR) thought to in- volve an accretion disk feeding a supermassive black hole. Interpretation of broad line measures within the 4DE1 formalism simplifies the apparent confusion among such data by contrasting and unifying properties of so-called high and low accreting Population A and B sources. H{beta} serves as an estimator of black hole mass, Eddington ratio and source rest frame, the latter a valuable input for Civ{lambda}1549 studies which allow us to isolate the blueshifted wind component. Optical and HST-UV spectra yield H{beta} and Civ{lambda}1549 spectra for low-luminosity sources while VLT-ISAAC and FORS and TNG-LRS provide spectra for high Luminosity sources. New high S/N data for Civ in high-luminosity quasars are presented here for comparison with the other previously published data. Comparison of H{beta} and Civ{lambda}1549 profile widths/shifts indicates that much of the emission from the two lines arise in regions with different structure and kinematics. Covering a wide range of luminosity and redshift shows evidence for a correlation between Civ{lambda}1549 blueshift and source Eddington ratio, with a weaker trend with source luminosity (similar amplitude outflows are seen over 4 of the 5 dex luminosity range in our combined samples). At low luminosity (z < 0.7) only Population A sources show evidence for a significant outflow while at high luminosity the outflow signature begins to appear in Population B quasars as well.
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