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Stellar Winds From Normal Stars


The effect of the normal star on the compact magnetized component is largely determined by the rate tex2html_wrap_inline9166 and velocity of stellar wind at infinity tex2html_wrap_inline9270 . For the majority of cases, we assume


where tex2html_wrap_inline9272 is the parabolic velocity at the stellar surface.

For Be-stars (i.e. those stars at the stage ``I'' whose mass increased during the first mass exchange), the wind velocity at infinity is taken to be equal to the Keplerian velocity  at the stellar surface


Thus, the lower stellar wind velocity leads to an effective increase of the captured mass rate by a secondary companion to such Be-stars.

The stellar wind rate at stage ``I'' is calculated as (de Jager 1980[41])


Here tex2html_wrap_inline9274 is a numerical coefficient.

For giant post-MS stars (stage ``II''), we assume tex2html_wrap_inline9276 and for massive star we take maximum wind rate between that given by de Jager's formula and that given by Lamers (1981)[94]:


For red supergiants at the asymptotic giant branch (AGB) stage, we use Reimers's formula (Kudritzki and Reimers, 1978[88])


When a massive star becomes a Wolf-Rayet star, its stellar wind can significantly increase (up to tex2html_wrap_inline9278 yr tex2html_wrap_inline8853 ). We parametrize such a wind  as


where the numerical coefficient is taken to be tex2html_wrap_inline9282 .

Mike E. Prokhorov
Sat Feb 22 18:38:13 MSK 1997