The nature of the near-infrared core source in 3C 433

We report the analysis of near-infrared (near-IR) imaging, polarimetric and spectroscopic observations of the powerful radio galaxy 3C 433 (z = 0.1016), obtained with the Hubble Space Telescope (HST) and the United Kingdom Infrared Telescope. The high spatial resolution of HST allows us to study the near-nuclear regions of the galaxy ( 10(4) km s(-1) (full width at half-maximum) to escape detection in our near-IR spectrum. Dichroic extinction is the most likely polarization mechanism because it is consistent with the various available extinction estimates. In this case, a highly ordered, coherent toroidal magnetic field must be present in the obscuring structure close to the nucleus.