Influence of an AGN complex photon field on the jet bulk Lorentz factor through Compton rocket effect

AGNs jets are known to display relativistic motion on parsec scales but the accelerating mechanism as well as the exact bulk Lorentz factor of the flow are still a matter of discussion. Under certain assumptions, a plasma can be accelerated to relativistic speeds through the Compton rocket effect. Here, we study this effect and the resulting bulk Lorentz factor in the complex environment of an AGN including various external sources. This is the proceedings to the IAU Symposium 313.