CAOSP abstracts, Volume: 56, No.: 1, year: 2026

Abstract: We present a re-evaluation of the relationship between the Mg II λ 2798 Å emission line and the 3000 Å continuum luminosity, including an analysis of the Baldwin Effect, using a sample of 40,685 radio-quiet quasars and 441 Flat Spectrum Radio Quasars (FSRQs). To address dispersion from AGN variability, we applied a binning technique after excluding over 3,000 radio-loud sources, resulting in a refined empirical correlation. Our findings reveal statistically significant differences in the slope of this relationship between RQ quasars and FSRQs, implying either intrinsic differences in their accretion disk spectra or a significant contribution from jet-induced continuum to the BLR ionization in FSRQs. Furthermore, our investigation of the Non-Thermal Dominance (NTD) parameter shows that a substantial fraction of both populations (43.8% of RQ quasars and 55.5% of blazars) exhibit NTD < 1. We interpret this in blazars as evidence that the accretion disk alone cannot power the BLR, while in RQ quasars, it may indicate BLR anomalies, continuum-line time lags, or UV continuum suppression by a strong corona. Finally, we demonstrate that the Baldwin Effect is a direct consequence of the fundamental line-continuum luminosity relationship.