A RADIO STUDY OF 3C 390.3 - A PRECESSING JET

Observations of the classical double radio galaxy 3C390.3 have been made to determine the spectral variations over the source at high radio frequencies. The corresponding spectral ages and the derived magnetic field directions are used to deduce the flow pattern of the radio-emitting plasma within the Np head. The results imply that (i) there is acceleration of material outside the hotspots in the Np head; (ii) the beam has changed direction by ~5° in the past 106yr or so; (iii) there is little spectral variation over the southern lobe. © Royal Astronomical Society • Provided by the NASA Astrophysics Data System.