The nonlinear solar dynamo and differential rotation: A Taylor number puzzle?

✍ Scribed by A. Brandenburg; D. Moss; G. Rüdiger; I. Tuominen

• Publisher: Springer
• Year: 1990
• Tongue: English
• Weight: 533 KB
• Volume: 128
• Category: Article
• ISSN: 0038-0938
• DOI: 10.1007/bf00154160

✦ Synopsis

We consider dynamically consistent mean-field dynamos in a spherical shell of incompressible fluid. The generation of magnetic field and differential rotation is parameterized by the ~-and A-effects, respectively. Extending previous investigations, we include now the eases of moderate and rapid rotation in the sense that the inverse Rossby number can approach or exceed unity." This can lead to disk-shaped ~2-contours, which are in better accordance with recent results of helioseismology than cylindrical Q-contours. On the other hand, in order to obtain eo)-dynamo cycles the Taylor number has to be so large, that eventually cylindrical f2-contours become unavoidable (cf. Taylor-Proudman theorem). We discuss the different possibilities in a state diagram, where the inverse Rossby number and the relative correlation length are taken as the elementary parameters for mean-field dynamos.