Synthesis of accretion disk and nonthermal source models for active galactic nuclei

Multiwavelength observations of 12 AGN are fitted with a model consisting of a nonthermal source surrounding an accretion disk around a massive black hole. It is demonstrated that the combined model provides a reasonable explanation of the observed intrinsic continuum. Values of the central engine's defining parameters are derived. The accretion disk radiates at 0.25-0.5 of the Eddington luminosity. The mass is of order 4 x 10 to the 8th solar for moderately luminous QSOs and Seyfert galaxies in the sample. The nonthermal source has a radius of about 70 Schwarzschild radii, a magnetic field of about 300 G, and an electron density of about 6 x 10 to the 6th/cu cm. The luminosities in the synchrotron, accretion disk, and scattered components are comparable. The electron distribution shape is consistent with injection of a power law with radiative losses dominating above a break energy and an energy-independent loss mechanism below the break energy. 58 refs