On the Baldwin effect in active galactic nuclei. II. Intrinsic spectral evolution

We suggest that the growth of the central black hole in active galactic nuclei (AGNs) due to the matter accreted over the AGN lifetime causes an evolution of the luminosity and spectrum. In a previous paper we have shown that the effective temperature of the UV continuum spectrum and the emission-line equivalent width are anticorrelated with the black hole mass. Here we estimate the change in the equivalent width of the emission lines due to the growth of the black hole mass caused by the accreted material and show that for several plausible accretion scenarios and effective-temperature models the evolving equivalent width is anticorrelated with continuum luminosity, implying that intrinsic evolution could contribute to the Baldwin effect.