Universal mass-luminosity relation for quasars and active galactic nuclei?

The masses of the central sources in quasars and active galaxies are determined, assuming the H..beta.. line velocity widths are gravitationally induced, and using the H..beta.. luminosities to estimate the distances of the broad-line regions (BLR) from the central sources. It is found that the continuum luminosities are proportional to the masses thus determined. The average ratio of the optical continuum luminosity to the Eddington luminosity is 0.01, with a scatter of less than a factor of 3, over four orders of magnitude in luminosity. In addition, it is shown that the ratio of X-ray to H..beta.. luminosity, which in this picture is proportional to the ionization parameter, is anticorrelated with the total luminosity. This supports previous findings that the ionization parameter in the BLR of Seyfert nuclei is higher than that of quasars.