2017MNRAS.464.1704G

We present a one-zone homogeneous self-consistent model for the multiwavelength emission features of PKS 1424+240 that allows the effects of automatic photon quenching to be studied. In the model, a steady γ-ray injection rate in the source is assumed and the non-linear time-dependent kinematic equations describing the evolution of both electrons and photons are then acquired; these self-consistently involve photon-photon interaction, synchrotron radiation of electron/positron pairs, inverse Compton scattering and synchrotron self-absorption. The model is applied to reproduce the multiwavelength spectrum of PKS 1424+240; our results indicate that the observed spectral energy distribution (SED) of PKS 1424+240 can be reproduced well in the case of both electron injection and photon injection. The injected electrons mainly influence the SED over radio, optical and X-ray bands and the SED in the high-energy γ-ray band is determined mainly by automatic photon quenching; in particular, the break form of the spectrum in the energy range >= a few GeV is caused by this. It should be noted that the observed SED from X-ray to γ-ray bands can be reproduced only through quenching, provided the observed data in the optical band are produced through some other mechanism, e.g. electron synchrotron radiation.