Theory of the differential rotation of a non-specific polytropic star

A. A. Bobnev

Abstract
Solutions (in general, numerical, but for a constant density, analytical) of the MHD problem for a rotating nonspherical star in the approximation of an ideal and perfectly conducting polytropic gas have been found. The ratio of electromagnetic forces to the gravitational ones has been assumed to be small, all three components of the magnetic field have been taken into account, and the components of velocity projected to the meridional plane are considerably smaller than the rotational velocity. The magnetic field vector on the star surface is zero. This surface is rotating as a rigid body while the inner layers rotate in a different manner. This differential rotation of the star is caused by the electromagnetic field. The constant component of the angular velocuty is given as must be larger than a certain value which depends on the characteristic magnitude of the electromagnetic field. Figs. 4, refs 5.