MARZIANI, PaolaPaolaMARZIANIdel Olmo, A.A.del OlmoMartínez-Carballo, M. A.M. A.Martínez-CarballoMartínez-Aldama, M. L.M. L.Martínez-AldamaSTIRPE, Giovanna MariaGiovanna MariaSTIRPENegrete, C. A.C. A.NegreteDultzin, D.D.DultzinD'Onofrio, M.M.D'OnofrioBon, E.E.BonBon, N.N.Bon2021-01-082021-01-0820190004-6361http://hdl.handle.net/20.500.12386/29607Context. The inter-line comparison between high- and low-ionization emission lines has yielded a wealth of information on the structure and dynamics of the quasar broad line region (BLR), including perhaps the earliest unambiguous evidence in favor of a disk + wind structure in radio-quiet quasars. <BR /> Aims: We carried out an analysis of the C IVλ1549 and Hβ line profiles of 28 Hamburg-ESO high-luminosity quasars and of 48 low-z, low-luminosity sources in order to test whether the width of the high-ionization line C IVλ1549 could be correlated with Hβ and be used as a virial broadening estimator. <BR /> Methods: We analyze intermediate- to high-S/N, moderate-resolution optical and near-infrared (NIR) spectra covering the redshifted C IVλ1549 and Hβ over a broad range of luminosity log L ∼ 44 - 48.5 [erg s<SUP>-1</SUP>] and redshift (0 - 3), following an approach based on the quasar main sequence. <BR /> Results: The present analysis indicates that the line width of C IVλ1549 is not immediately offering a virial broadening estimator equivalent to Hβ. At the same time a virialized part of the BLR appears to be preserved even at the highest luminosities. We suggest a correction to FWHM(C IVλ1549) for Eddington ratio (using the C IVλ1549 blueshift as a proxy) and luminosity effects that can be applied over more than four dex in luminosity. <BR /> Conclusions: Great care should be used in estimating high-L black hole masses M<SUB>BH</SUB> from C IVλ1549 line width. However, once a corrected FWHM C IVλ1549 is used, a C IVλ1549-based scaling law can yield unbiased M<SUB>BH</SUB> values with respect to the ones based on Hβ with sample standard deviation ≈0.3 dex.STAMPAenArticle10.1051/0004-6361/2019352652-s2.0-85069440905000474197300001https://www.aanda.org/articles/aa/abs/2019/07/aa35265-19/aa35265-19.htmlhttps://arxiv.org/abs/1905.006172019A&A...627A..88MFIS/05 - ASTRONOMIA E ASTROFISICA