Axisymmetrical models for the origin and shaping of proto-planetary nebulae |
| |
| Authors: | G Pascoli |
| |
| Institution: | (1) Department of Physics, Faculté des sciences, 33 rue Saint Leu, Amiens, 80039 Cedex, France |
| |
| Abstract: | Axisymmetrical models for protoplanetary nebulae are produced. We discuss the mechanism for mass loss from evolved cool stars and the characteristics of the gas outflow. By using two-dimensional magnetohydrodynamics, we find that the gas is preferentially ejected in a so-called equatorial plane. For a grid of models, the expansion velocities are found to be of the order ofv
escape/2 and the mass loss rates tilde 10–5-10–4
M
 /year which appear consistent with the available observational data. Magnetic fields intensities in the 10–4 to 10–3 gauss range are obtained in circumstellar envelopes, in good agreement with observations (Nedoluha and Bowers, 1992). |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
