The IUE Spectrum of the Planetary Nebula NGC 6751

Abstract

We present the first high-dispersion lUE short-wavelength (SWP) spectrum of NGC 6751 (029.2 -05.9) from which log N_c = 3.9±0.05 cm^-3, terminal wind velocity v∞ = 2450±150 km s^-1, and a maximum mass-loss rate of M^ṡ_(max) 7.9 × 10^-8 M_sun yr^-1 are determined. Emission-line fluxes from low-dispersion spectra for the epochs 1981 and 1994 are presented which suggest some changes may have occurred. The C III] λλ1907, 1909 doublet displays an unusual triple-peaked profile in the high-resolution spectrum. The IUE range is characterized by a rich stellar spectrum of carbon lines at various stages of ionization and few nebular lines.