Magnetic dynamo action in astrophysical turbulence
نویسندگان
چکیده
We investigate the structure of magnetic field amplified by turbulent velocity fluctuations, in the framework of the kinematic Kazantsev-Kraichnan model. We consider Kolmogorov distribution of velocity fluctuations, and assume that both Reynolds number and magnetic Reynolds number are very large. We present the full numerical solution of the model for the spectra and the growth rates of magnetic fluctuations. We consider astrophysically relevant limits of large and small magnetic Prandtl numbers, and address both helical and nonhelical cases. Subject headings: magnetic fields — magnetohydrodynamics: MHD — turbulence
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تاریخ انتشار 2009