Magnetic buoyancy and magnetorotational instabilities in stellar tachoclines for solar- and antisolar-type differential rotation

At latitudes where the vertical rotation gradient is negative, vigorous magnetorotational instability for even weak (Lt1 kG) toroidal fields prevents such storage. We infer from these results that for stars with solar-type latitudinal differential rotation (fast equator, slow poles), any starspots present should be found in low latitudes, similar to the Sun. For antisolar differential rotation, any spots present should be found in mid- and high latitudes, perhaps with a peak of occurrence near 55°.

These results hopefully provide some guidance for making and interpreting observations of stellar activity and differential rotation on stars with convection zones and tachoclines.