Equilibrium models for luminous helium stars
نویسندگان
چکیده
منابع مشابه
Full evolutionary models for PG 1159 stars . Implications for the helium - rich O ( He ) stars .
Aims. We present full evolutionary calculations appropriate to post-AGB PG1159 stars for a wide range of stellar masses. Methods. We take into account the complete evolutionary stages of PG1159 progenitors starting from the Zero Age Main Sequence. We consider the two kinds of Born Again Scenarios, the very late thermal pulse (VLTP) and the late thermal pulse (LTP), that give rise to hydrogen-de...
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We study the effect of microturbulence in the line formation calculations of H and He lines, in the parameter range typical for O and early B stars. We are specially interested in its effect on the determination of stellar parameters: Teff , log g and specially on the He abundance. We first analyze the behaviour of H and He model lines between 4 000 and 5 000 Å with microturbulence and find tha...
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Test particles infalling from infinity onto a compact spherical star with a mildly super-Eddington luminosity at its surface are typically trapped on the “Eddington Capture Sphere” and do not reach the surface of the star. The presence of a sphere on which radiation pressure balances gravity for static particles was first discovered some twenty five years ago. Subsequently, it was shown to be a...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 1988
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/235.1.203