The results of calculations of gas emission spectra with both central and extended sources of ionization have been compared to the ratio of line intensities observed in the extended narrow line region of NGC1068. The origin of an extended structure of anomalous strength in the $[OIII] lambda 5007$ and $[NeV] lambda 3425$ lines found by Evans & Dopita (1986) and Bergeron et al. (1989) could be due to an additional stellar source of gas ionization located at a distance 1-2 kpc from the nucleus.
Download