André Maeder, Cyril Georgy, Georges Meynet, Sylvia Ekström
We examine some properties of stars evolving close to the classical Eddington
limit for electron-scattering opacity, when these stars maintain a chemically
homogeneous structure as a result of mixing and/or mass loss.
We consider analytical relations and models computed with the Geneva code.
Homologous, chemically homogeneous stars evolving with a constant Eddington
factor obey a relation of the form mu^2 M = const. This applies, for example,
to Wolf-Rayet (WR) stars in stages without hydrogen. The value of the constant
may depend on the metallicity, initial mass, evolutionary stage, and physical
processes included in the considered homologous evolutionary sequence. An
average value of the constant between 20 and 40 in solar units is consistent
with the masses of Galactic WR stars.
View original:
http://arxiv.org/abs/1201.5013
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