Electron Densities, Radial and Terminal Wind Velocities for the Planetary Nebula NGC 6302 and Its O VI-Type Binary Nucleus

Abstract

Archival high- and low-dispersion IUE spectra of NGC 6302 and its nucleus have been analyzed. The spectra in the NEWSIPS format reveal many high-excitation emission features, including stellar O V, O VI, O VII, and O VIII that identify the nucleus as a new member of the ``O VI sequence.'' Fe II features that are resonantly excited by O VI λ1032 are also observed. Other high-excitation species include [Ne IV], [Ne V], [Mg VI], and [Si VII]. Electron densities were determined from C III], N III], N IV], and [Ne IV] and are compared to IR [Ne V] densities. Radial velocities of strong emission features cluster around -55 km s^-1 except for the Bowen O III and [O II] lines that show large positive radial velocities. Results from IUE, optical, ground-based IR, and KAO IR data are summarized. A relatively low terminal wind velocity of -520+/-200 km s^-1 was estimated from the P Cygni profile of the C IV λ1548 feature. A G-type companion to the very hot white dwarf central star is indicated by the LWR/LWP low-dispersion spectra.