X-ray and radio emission in the nuclei of radio galaxies and the disk-jet connection

It appears that relativistic jets are produced by accreting black holes. We might therefore expect that events observed in jets, such as the appearance of bright radio knots moving at apparent superluminal speeds, originate as disturbances in the central engine. This is observed in a number of compact X-ray binary systems in our Galaxy, manifested as changes in the X-ray emission state followed by superluminal ejections. The author and collaborators have detected somewhat similar events in the radio galaxies 3C 120 (type Fanaroff-Riley I) and 3C 111 (FR II). The data both confirm the disk-jet connection in accreting supermassive black holes and provide constraints on the structure of the jet between the central engine and the millimeter-wave core.