Spectral Signatures of Jet-driven Shocks in Active Galactic Nuclei

Abstract

It is now clear that jet-driven shocks in active galaxies are responsible for an important fraction of the emission of the extended narrow-line regions (at all wavelengths). The remainder arises from photoionisation by UV photons originating at the active nucleus itself. This review examines the spectral and dynamical signatures of jet-driven shocks in these environments, and shows how these can be used to constrain the shock velocities, the parameters of the jet, the galactic or circumgalactic medium and the nature of the central engine.