Recombination spectrum and reddening in NGC 1068.
Persson, S. E.; Matthews, K.; Soifer, B. T.; Smith, A. M.; Oke, J. B.; Torres-Peimbert, S.; Wynn-Williams, C. G.; Neugebauer, G.; Daltabuit, E.; Morton, D.; Becklin, E.
United States, Australia, Mexico
Abstract
Measurements of the emission-line intensities of NGC 1068 have been made over the wavelength range extending from rest wavelengths equal to 1216 A to 1.875 micron. The data, plus other available emission-line data, can be explained in terms of a simple model where the emission lines are formed in an H II region, and the line ratios are consistent with those predicted by standard radiative recombination theory and reddening corresponding to 0.4 mag. The continuum flux is seen to consist of a galaxy component plus a nonstellar component which dominates the observed flux in the ultraviolet. The observed ultraviolet continuum does not show an absorption dip caused by the intertellar 2200 A feature nor does it contain enough energy to power the observed infrared flux.