MHD solutions for proto-planetary nebulae
Por:
García-Segura G., López J.A., Franco J.
Publicada:
1 ene 2003
Resumen:
This paper provides solutions for the origin of post-AGB winds, their acceleration up to high speed, and the subsequent formation of extremely collimated proto-planetary nebulae. Several wind models with terminal velocities from a few tens of km s-1 up to 103 km s-1 are calculated, which produce proto-planetary nebulae with linear momentum in the range 1036-1040 g cm s-1 and with kinetic energies in the range 1042-1047 erg. These results match available observations of proto-planetary nebulae. In the present simplistic scheme, the driver of the wind is just the magnetic pressure at the stellar surface. Other forces are not taken into account in this study, except gravity. We conclude that mass-loss rates of post-AGB stars and transition times from late AGB up to planetary nebula central stars could be directly linked with the production of magnetic field at the stellar core. As an example, mass-loss rates as large as 8 × 10-5 M. yr-1 and transition times as short as 5,000 years are predicted.
Filiaciones:
García-Segura G.:
Instituto de Astronomía-UNAM, Ensenada, Mexico
López J.A.:
Instituto de Astronomía-UNAM, Ensenada, Mexico
Franco J.:
Instituto de Astronomía-UNAM, Mexico DF, Mexico
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