Published online by Cambridge University Press: 25 May 2016
In powerful FRII radio galaxies and quasars the polarization of the two radio lobes is often very asymmetric and strongly correlated with jet sidedness. These sources usually have one-sided jets and the lobe on the jet side depolarizes more slowly than the one on the counter-jet side (Laing 1988; Garrington et al. 1988). This correlation can be interpreted in terms of depolarization of the receding lobe by a halo of hot gas surrounding the radio source and is in the expected sense if the jet asymmetry is due to Doppler boosting.