Radio source asymmetries and unified schemes

The angular asymmetries and relative separations of the hot-spots of FRII radio sources in a complete sample of 3CR sources have been used to study the effects of misalignment of the directions of ejection and the velocities of the hot-spots, in conjunction with a test of Barthel's models which unify radio galaxies and quasars. It is found that the observed distributions of asymmetry angles in radio galaxies and quasars are consistent with unified models, and with the source components being ejected uniformly within an angle of 6–7° about the source axis. The separation quotients are also consistent with the scheme if the velocities of the hot-spots have a broad distribution about a mean of 0.2c, with values extending at least up to 0.4c.