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Particle transport and surface abundance inhomogeneities

Published online by Cambridge University Press:  25 May 2016

G. Michaud
G. Michaud*
Affiliation:
Departement de Physique Université de Montréal and CERCA

Abstract

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The various mechanisms leading to the appearance of horizontal inhomogeneities at the surface of ApBp stars are critically reviewed. The effect of magnetic fields is essential but is it more to control locally, on the surface, the appearance of anomalies that are caused by the vertical transport of particles, or is it to create directly the horizontal inhomogeneities by horizontal transport? The time scales for horizontal and vertical transport will be discussed in this context.

The processes discussed include: a) ambipolar diffusion of protons and hydrogen in the presence of magnetic fields; b) the guiding of diffusion by magnetic fields; c) the horizontal component of radiative accelerations; d) mass loss; e) light induced drift.

Type
Session III: “Photospheric Phenomena: Results”
Information
Symposium - International Astronomical Union , Volume 176: Stellar Surface Structure , 1996 , pp. 321 - 328
Copyright
Copyright © Kluwer 1996 

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