Generation of magnetic fields by large-scale vortices in rotating convection.

  title={Generation of magnetic fields by large-scale vortices in rotating convection.},
  author={C{\'e}line Guervilly and David W. Hughes and Chris A. Jones},
  journal={Physical review. E, Statistical, nonlinear, and soft matter physics},
  volume={91 4},
We propose a self-consistent dynamo mechanism for the generation of large-scale magnetic fields in natural objects. Recent computational studies have described the formation of large-scale vortices in rotating turbulent convection. Here we demonstrate that for magnetic Reynolds numbers below the threshold for small-scale dynamo action, such turbulent flows can sustain large-scale magnetic fields, i.e., fields with a significant component on the scale of the system. 

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