Inverse Compton scattering model for gamma-ray production in MeV blazars

Abstract

It is proposed that the spectra of so called 'MeV blazars' can be explained in terms of previously developed models of the external comptonization of accretion disk radiation provided that the structure of the inner and outer parts of the accretion disk is different. The electron acceleration is saturated by the inverse Compton losses in the inner geometrically thick disk and the outer geometrically thin disk at different maximum energies which causes the appearance of two spectral components, one strongly peaked in the MeV energy range and the second one of a power law type extending through the GeV energy range. The spectra, computed in terms of such a simple geometrical model, are in a good agreement with observations of the MeV blazar PKS0208-512. They are consistent with the transient appearance of a strong MeV peak, the power law spectrum in the EGRET energy range, and a possible cut-off at high energies.