Simultaneous IUE and ground-based observations of V923 Aquilae.
Ringuelet, A. E.; Rovira, M.; Sahade, J.; Kondo, Y.; Fontenla, J. M.
Argentina
Abstract
Simultaneous IUE and ground-based observations of V 923 Aquilae carried out in July 1981 are used to propose a model of the extended envelope of this Be star with a transition region relatively close to the star, where the highly ionized species would be formed. The shell photographic and ultraviolet lines of Fe II and the photographic lines of Ca II and Na I would originate in regions exterior to the transition zone. As for the faint Fe II and Ni II emissions that are displayed by the photographic spectrum, the possible regions where they could form are considered. The zone of temperature rise between the star and the transition region appears as more likely; plans to check this model numerically are being formulated. The star is characterized by variable mass-ejection, and is not a cyclic V/R variable.