The magnetic shear-current effect: generation of large-scale magnetic fields by the small-scale dynamo
نویسندگان
چکیده
J. Squire1,3† and A. Bhattacharjee2,3 TAPIR, Mailcode 350-17, California Institute of Technology, Pasadena, CA 91125, USA Department of Astrophysical Sciences and Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543 Max Planck/Princeton Center for Plasma Physics, Department of Astrophysical Sciences and Princeton Plasma Physics Laboratory, Princeton University, Princeton, NJ 08543, USA
منابع مشابه
Generation of Large-Scale Magnetic Fields by Small-Scale Dynamo in Shear Flows.
We propose a new mechanism for a turbulent mean-field dynamo in which the magnetic fluctuations resulting from a small-scale dynamo drive the generation of large-scale magnetic fields. This is in stark contrast to the common idea that small-scale magnetic fields should be harmful to large-scale dynamo action. These dynamos occur in the presence of a large-scale velocity shear and do not require...
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Nonhelical shear dynamos are studied with a particular focus on the possibility of coherent dynamo action. The primary results—serving as a follow up to the results of Squire & Bhattacharjee—pertain to the “magnetic shearcurrent effect” as a viable mechanism to drive large-scale magnetic field generation. This effect raises the interesting possibility that the saturated state of the small-scale...
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