A extended ionizing radiation cone from the nucleus of the Seyfert 2 galaxy NGC 1068

Abstract

CCD images of the Seyfert 2 galaxy NGC 1068 have been made through narrow interference filters isolating the emission lines of Ha + [N n] 226548, 6583 and of [O m] 25007. A simple "ionization map" obtained from these images has revealed a cone-shaped region of high-ionization gas emanating from the nucleus into the surrounding regions. This cone lies along the axis of the radio jet seen in this galaxy. An ionizing radiation cone like this is predicted by a number of models for Seyfert 2 nuclei, in particular the " hidden Seyfert 1 " picture suggested for NGC 1068 by recent spectropolarimetric observations.