Stability of the differential rotation of stars

The difference in rotation laws between top and bottom of the solar convection zone as revealed by helioseismology may result from an instability switched on near the bottom. The conclusion results from the analysis of the differential rotation stability. The instability is sensitive to both differential rotation magnitude and details of the latitudinal profile of the angular velocity. It can be active in subadiabatically stratified fluids only. The instability does not develop in the bulk of convection zone but may switch-on in the region of penetrative convection near its base. The growth rates and symmetry types of most rapidly growing disturbances in dependence on the differential rotation parameters are computed.