Tauri stars rotate differentially ?
نویسنده
چکیده
We compute the rotation profile of a T Tauri star from the balance between the different components of the Reynolds stress and the meridional circulation. We first use a simple model to study the influence of the meridional flow on the differential rotation and vice versa. A more realistic model is then presented, which includes the stratification of the turbulence derived from a stellar model. We find that for a strictly spherical star without any latitudinal gradients in temperature, density and pressure the rotation is very close to the rigidbody state. We conclude that the stellar magnetic field must be generated by an 2rather than an -dynamo. It must thus have non-axisymmetric geometry and will not show cyclic behaviour.
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