Surface differential rotation is observed on stars such as the Sun when the angular velocity varies with latitude. Typically the angular velocity decreases with increasing latitude. However the reverse has also been observed, such as on the star designated HD 31993.) The first such star, other than the Sun, to have its differential rotation mapped in detail is AB Doradus.
The underlying mechanism that causes differential rotation is turbulent convection inside a star. Convective motion carries energy toward the surface through the mass movement of plasma. This mass of plasma carries a portion of the angular velocity of the star. When turbulence occurs through shear and rotation, the angular momentum can become redistributed to different latitudes through meridional flow.
The interfaces between regions with sharp differences in rotation are believed to be efficient sites for the dynamo processes that generate the stellar magnetic field. There is also a complex interaction between a star's rotation distribution and its magnetic field, with the conversion of magnetic energy into kinetic energy modifying the velocity distribution.
Other articles related to "differential rotation, rotation":
... See also Solar rotation On the Sun, the study of oscillations revealed that rotation is roughly constant within the whole radiative interior and variable with ... The Sun has an equatorial rotation speed of ~2 km/s its differential rotation implies that the angular velocity decreases with increased latitude ... The poles make one rotation every 34.3 days and the equator every 25.05 days, as measured relative to distant stars (sidereal rotation) ...
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