Abstract
Specific features both of continua and of line spectra of WR and P Cygni type stars can probably be explained if an extensive deceleration zone is proposed to exist in their stellar winds. The outflowing matter is first accelerated near the stellar surface, then follows the deceleration of the flow and after that the final acceleration of the outflowing matter takes place (i.e. the wind has an ADA-structure: acceleration-deceleration-acceleration). Such a structure of the wind probably arises due to the multiscattering of photons in the envelope having two detached shells, which are optically thick in resonance lines (these shells can form if ionization stratification is present in the envelope).
Publisher
Cambridge University Press (CUP)