Systematically smaller single-epoch quasar black hole masses using a radius–luminosity relationship corrected for spectral bias

Determining black hole masses and accretion rates with better accuracy precision is crucial for understanding quasars as a population. These are fundamental physical properties that underpin models of active galactic nuclei. A primary technique to measure the mass employs reverberation mapping low-redshift quasars, which then extended via radius-luminosity relationship broad-line region estimate based on single-epoch spectra. An updated incorporates flux ratio optical Fe ii H$\beta$ ($\equiv \mathcal{R}_{\rm Fe}$) correct bias in more highly accreting systems have smaller line-emitting regions than previously realized. In this current work, we demonstrate quantify effect using Fe-corrected estimation by employing archival data sets possessing rest-frame spectra over wide range redshifts. We find failure use radius predictor results overestimated most quasars. Their rate measures ($L_{\rm Bol}/ L_{\rm Edd}$ $\dot{\mathscr{M}}$), similarly underestimated. The strongest Fe-emitting belong two classes: high-z spectra, given their extremely high luminosities, require rates, low-z analogs, low holes masses, must meet survey limits. classes corrections downward about factor two, average. strengthen association dominant Eigenvector 1 parameter $\mathcal{R}_{\rm Fe}$ process.