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تسجيل مستخدم جديدAbundance distributions over the surfaces of magnetic ApBp stars: theoretical predictions
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G. Alecian
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Recently published empirical abundance maps, obtained through (Zeeman) Doppler mapping (ZDM), do not currently agree with the abundance structures predicted by means of numerical models of atomic diffusion in magnetic atmospheres of ApBp stars. In a first step towards the resolution of these discrepancies, we present a state of the art grid of equilibrium abundance stratifications in the atmosphere of a magnetic Ap star with T_eff = 10000 K and log g = 4.0. A description of the behaviour of 16 chemical elements including predictions concerning the over- and/or under-abundances over the stellar surface is followed by a discussion of the possible influence of presently neglected physical processes.
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Numerical models for the atmospheres of magnetic ApBp stars have in the past dealt only with centred dipole magnetic field geometries. These models include atomic diffusion that stratifies the abundances of metals according to the local magnetic fiel
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