Bibcode
Villaver, E.; García-Segura, G.; Manchado, A.
Referencia bibliográfica
Gravitational Collapse: From Massive Stars to Planets. / First Astrophysics meeting of the Observatorio Astronomico Nacional. / A meeting to celebrate Peter Bodenheimer for his outstanding contributions to Astrophysics. (Eds. G. García-Segura, G. Tenorio-Tagle, J. Franco, & H. W. Yorke) Revista Mexicana de Astronomía y Astrofísica (Serie de Conferencias) Vol. 22, pp. 140-143 (2004) (http://www.astroscu.unam.mx/~rmaa/)
Fecha de publicación:
12
2004
Número de citas
3
Número de citas referidas
2
Descripción
A large fraction of all stars, after experiencing heavy winds at the end
of the Asymptotic Giant Branch (AGB) phase, leave behind a core that is
below the Chandrasekhar mass limit. This core eventually photoionizes
the stellar ejecta giving birth to a planetary nebula (PN). PN and AGB
stars are therefore the remnants of stars that through their winds
contribute to the chemical enrichment of the ISM with elements He, C, N
and O. We have explored the impact of such winds in the ISM and in the
formation and evolution of the circumstellar envelopes around AGB stars
and PN shells. In our simulations, we find that huge shells (up to 2.5
pc in radius) are formed as a consequence of the mass-loss during the
early AGB phase. When the star is at rest with respect to the ISM, these
shells contain a large fraction of ISM material that has been swept up
by the stellar wind. We find that when the star is moving and the ram
pressure is high enough, significant dispersal between the stellar
ejecta and the ISM material still takes place due to instabilities,
however, the mass and the size of the envelope are highly reduced due to
ram pressure stripping.