Outflowing disk formation in B[e] supergiants due to rotation and bi-stability in radiation driven winds

¹ Departamento de Física y Meteorología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile e-mail: michel.cure@uv.cl
² Departamento de Matemáticas, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina e-mail: drial@dm.uba.ar
³ Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, La Plata, Buenos Aires, Argentina e-mail: lydia@fcaglp.unlp.edu.ar

Received: 11 November 2004
Accepted: 14 March 2005

Abstract

The effects of rapid rotation and bi-stability upon the density contrast between the equatorial and polar directions of a B[e] supergiant are re-investigated. Based on a new slow solution for different high rotational radiation-driven winds and the fact that bi-stability allows a change in the line-force parameters (α, k, and δ), the equatorial densities are about 10²–10⁴ times higher than the polar ones. These values are in qualitative agreement with the observations.