Vuillaume, Thomas

A stratified jet model for the high energy emission of AGN: influence of the anisotropic Inverse Compton effect.

Author list: T. Vuillaume, G. Henri, P-O. Petrucci

It is now granted that the gamma ray emission of AGNs arise predominantly from Inverse Compton scattering of low energy photons by highly relativistic particles in the jet. But the exact source and location of these photons is still a matter of discussion. For BL Lac type objects, the main contribution is probably provided by synchrotron radiation and the high-energy emission is thus dominated by Synchrotron Self Compton (SSC) process. For luminous quasars however, the emission from the accretion disc and the reprocessed components (Broad Lines and molecular torus) is probably significant and can even be dominant. Whereas diffuse component is approximately isotropic, the emission from the accretion disc is highly anisotropic and the effect on Inverse Compton emission can be very important. The leptonic model we have been developing takes into account a multi-zone emission as well as the geometry of the disc and thus the anisotropy of the emission. We illustrate the consequences of anisotropy in the vicinity of the accretion disk on several examples that could be relevant to AGN spectra and variability, and present some fitted spectra.