Hyperdiffusion in nonlinear large- and small-scale turbulent dynamos.

  title={Hyperdiffusion in nonlinear large- and small-scale turbulent dynamos.},
  author={Kandaswamy Subramanian},
  journal={Physical review letters},
  volume={90 24},
  • K. Subramanian
  • Published 2 March 2003
  • Physics, Medicine
  • Physical review letters
The generation of large-scale magnetic fields is generically accompanied by the more rapid growth of small-scale fields. The growing Lorentz force due to these fields backreacts on the turbulence to saturate the mean-field and small-scale dynamos. For the mean-field dynamo, in a quasilinear treatment of this saturation, it is generally thought that, while the alpha effect gets renormalized and suppressed by nonlinear effects, the turbulent diffusion is left unchanged. We show here that this is… 

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