The Spectrum of NGC 7027
Feibelman, W. A.; Aller, L. H.; Keyes, Charles D.
United States
Abstract
IUE and echelle spectrograph observations of the planetary nebular NGC 7027 are analyzed to obtain nebular plasma diagnostics and chemical abundances. It is found that most of the nebular plasma has a density of about 60,000/cu cm and a temperature of about 14,000 K. The results suggest that the stellar radiation field is greatly enhanced shortward of 130 A because of a dense non-LTE wind. It is found that the chemical composition is that of a normal C-rich object, rather than that of a N-rich object.