Disk formation in Be and B[e] stars.

CURÉ, M.; CIDALE, L.; VENERO, R.; RIAL, D.

Pucón, Chile

Congreso; XI Reunión Regional Latinoamericana de Astronomía y Astrofísica; 2005

IAU

The inclusion of rotation in the hydrodynamic equations of  radiation driven winds in a rapidly rotating star yields to a new solution (Curé, M., 2004, ApJ, 614, 929). Combining this new solution (slow solution) and the standard solution (fast  solution) to describe the wind structure of a rotating star, a hybrid  wind model is obtained. The polar wind is described by the fast solution while the equatorial flow, by the slow solution. We compute simultaneously the line-force parameters and the density contrast between polar and equatorial regions. In the equatorial  region  close to the star ( < 2 R*) we obtain density values 1000 times greater  than the ones obtained in the polar region. In external regions the density  contrast is around 10. We propose these solutions to explain the disk wind  formation in B[e] stars. In the case of Be stars, the computed density  contrast is between 10 and 30.