Dynamo driven by weak plasma turbulence
نویسندگان
چکیده
The dynamo mechanism driven by weak plasma turbulence, called the p-ω dynamo, is studied. Under the assumption of the uniform rotation of a celestial body, a dynamo equation is derived from the magnetic induction equation based on mean field electrodynamics. It is well known that differential rotation is indispensable for an α-ω dynamo to be operative. In contrast to the α-ω dynamo model, no matter if the rotation angular velocity is uniform or not, no matter in the absence or the presence of the convection, the p-ω dynamo is operative. The coupling between uniform rotation and plasma turbulence waves can also produce source terms in the dynamo equation which lead to the generation of a poloidal and toroidal field. The existence of differential rotation will evidently enhance the action of the p-ω dynamo. We present a complete uniformrotational solution of the dynamo equation here, and dynamo solutions for several types of differential rotation are given. Finally, we discuss the physical nature of these dynamo solutions in Sect. 5.
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