Spectral Energy Distribution (119–685 nm) in 16 Shell Stars and a Tentative Model for Accreting be Stars

Abstract

I.U.E. low-dispersion spectra and spectral scans made with the Lick Observatory IDS scanners have been combined for 16 shell stars. Eleven objects can be represented by Kurucz model atmospheres, although some of them display strong shell-type line spectra. Five among them are known binaries. The six remaining objects (all interacting binaries) display complex spectra. A model involving continuum and line radiation from a hydrogen cloud surrounding the accreting component is proposed. A generalization of this model with optically thick segments of the cloud promises to explain even more exotic objects such as β Lyrae, W Serpentis and possibly ∊ Aurigae.