Compton and Synchrotron Emissions from Pair Cascades in AGN Environments

Recent detections of very-high-energy gamma-ray blazars which do not belong to the high frequency peaked BL Lac class, suggest that gamma-gamma absorption and pair cascade supported by Compton upscattering might occur in those objects. We investigated the Compton emission from VHE gamma-ray induced pair cascades and demonstrated that this emission can explain the Fermi fluxes and spectra of radio galaxies Cen A and NGC 1275. We demonstrate that the magnetic field from the AGN environment can not be determined from a fit of the cascade emission to the gamma-ray spectrum alone, and the degeneracy can only be lifted if the synchrotron emission from the cascades is observed as well. We point out that the cascade synchrotron emission may produce spectral features reminiscent of the big blue bump observed in the spectral energy distributions of several blazars, and illustrate this idea for 3C 279.