What does CIVλ1549 tell us about the physical driver of the Eigenvector quasar sequence

Broad emission lines in quasars enable us to "resolve" structure and kinematics of the broad-line emitting region (BLR)thought to involve 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 being 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-luminosit 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 four of the five dex luminosity ranges in our combined samples). At low luminosity (z less than or similar to 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.