It has been shown that rotation may indirectly have a large effect on the latitudinal abundance distribution of metals via gravity darkening. Indeed, the effect is possibly active in all the model stars considered here. Stars of low metallicity are particularly prone to this effect. If the mass loss of the star is strongly metallicity dependent, then the effect in the outer layers may be curtailed somewhat. This may lead to an extra mass-loss rate enhancement in the equatorial plane.
Although several major points regarding the effects of meridional diffusion of ions toward the equator have simply been touched on, the principle of metallic latitudinal distribution asymmetries has at least been put on quantitative basis.
© European Southern Observatory (ESO) 1999
Online publication: December 4, 1998