PW Vulpeculae: A Nova with Nearly Solar Abundances

Abstract

Optical spectrophotometry of PW Vulpeculae is combined with ultraviolet data to estimate electron temperatures, densities, and abundances in the ejecta of this slow classical nova. The reddening, the distance, and the evolution of the ultraviolet spectrum are discussed. Abundances are nearly solar, with the exception of nitrogen, which is substantially higher. Although neon has been reported to be enhanced in several novae, it does not seem to be the case for PW Vul. Photoionization model calculations of the ejecta that give a reasonable match of the observed emission spectrum are presented. A strong featureless continuum shows that very hot, presumably shock-heated, gas plays a major role in determining the energetics of this nova. Emission from this hot gas is responsible for the ionization of the nebular gas. A calculation of the masses of both the hot coronal gas and the cooler nebular gas shows that the former may account for most of the mass of the ejecta.