Observational Constraints for Solar-Type Dynamos
The different phenomena of solar and stellar activity are generally considered to have its origin in the turbulent convective envelopes of these stars. We will discuss how the problem can be treated in the framework of the mean-field concept.
The solar differential rotation can be produced by Reynolds stresses parameterizing the influence of rotation on convection. Some forms of these stresses give the observed solar differential rotation and other related observed phenomena, including the internal angular velocity in the convection zone, obtained by helioseismology.
As a further problem we investigate whether it is possible to produce the observed geometry of the mean oscillating magnetic field of the Sun when taking into account the constraints given by differential rotation and mean helicity of convection, and furthermore, whether this magnetic field produces correctly the observed cyclic flows, e.g. the so-called torsional oscillations.
Some solutions of these problems will be summarized. With simplified examples it is further discussed how the procedure can be extended to different types of convection zones, in order to derive observable properties of other stars with convective envelopes.
KeywordsSolar Phys Lorentz Force Convection Zone Differential Rotation Torsional Oscillation
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