Magnetic drift processes in differentially rotating turbulence
نویسنده
چکیده
The mean electromotive force is considered in a differentially rotating fluid taking into account stretching of the turbulent magnetic field. Calculations are performed by making use of the second order correlation approximation. Nonuniformity of the angular velocity leads to specific drift processes in the azimuthal direction. Due to this drift the magnetic field can rotate with a somewhat different angular velocity than the fluid. Differential rotation can also lead in a new instability of a non-axisymmetric mean field. Regardless of the law of the differential rotation this instability can result in an exponential amplification of the field.
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