Spectral modelling of gamma-ray blazars

We present model calculations reproducing broadband spectra of γ-ray blazars by a relativistic leptonic jet, combining the EIC and the SSC model. To this end, the evolution of the particle distribution functions inside a relativistic pair jet and of the resulting photon spectra is investigated. Inverse-Compton scattering of both external (EIC) as well as synchrotron photons (SSC) is treated using the full KleinNishina cross-section and the full angle-dependence of the external photon source. We present model fits to the broadband spectra of Mrk 421 and 3C279 and the X-ray and γ-ray spectrum of PKS 1622-297. We find that the most plausible way to explain both the quiescent and the flaring states of these objects consists of a model where EIC and SSC dominate the observed spectrum in different frequency bands. For both Mrk 421 and 3C279 the flaring states can be reproduced by a harder spectrum of the injected pairs.