Hostname: page-component-78c5997874-ndw9j Total loading time: 0 Render date: 2024-11-08T07:25:46.589Z Has data issue: false hasContentIssue false

New Results in Evolution in the Upper HRD

Published online by Cambridge University Press:  03 August 2017

E.I. Staritsin*
Affiliation:
Astronomical Observatory, Ural State University, Sverdlovsk, U.S.S.R.

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

A theoretical interpretation of the observed upper luminosity limit is suggested here. Staritsin (1989) considered the core hydrogen and helium burning stages in a 64 M star. Mixing in a semi-convection zone in a diffusion approximation (Staritsin, 1987) and mass loss by stellar wind (de Jager et al., 1988) were taken into account. During MS evolution the star looses half of its initial envelope. After MS evolution an intermediate convective zone appears. The hydrogen content in the shell source increases. As a result, the star burns helium in its blue supergiant stage. After the hydrogen content in the envelope has decreased to 10% of its mass, the star looses mass with Wolf-Rayet mass loss rates according to de Jager et al. (1988). The star has a WR character during 5% of its full life time.

Type
Session VII. Evolution
Copyright
Copyright © Kluwer 1991 

References

Humphreys, R.M. 1987, Publ. Astron. Soc. Pacific 99, 5.CrossRefGoogle Scholar
de Jager, C., Nieuwenhuijzen, H., van der Hucht, K.A. 1988, Astron. Astrophys. Suppl. 72, 259.Google Scholar
Staritsin, E. 1987, Nauch. Inf. Astron. Sov. 63, 97.Google Scholar
Staritsin, E. 1989, Astron. Zh. 66, 975 (= Sov. Astron. 33, 503).Google Scholar