The turbulent magnetic prandtl number of mhd turbulence in disks

  title={The turbulent magnetic prandtl number of mhd turbulence in disks},
  author={Xiaoyue Guan and Charles F. Gammie},
  journal={The Astrophysical Journal},
  • X. Guan, C. Gammie
  • Published 22 March 2009
  • Physics, Geology
  • The Astrophysical Journal
The magnetic Prandtl number PrM is the ratio of viscosity to resistivity. In astrophysical disks the diffusion of angular momentum (viscosity) and magnetic fields (resistivity) are controlled by turbulence. Phenomenological models of the evolution of large-scale poloidal magnetic fields in disks suggest that the turbulent magnetic Prandtl number PrM,T controls the rate of escape of vertical field from the disk; for PrM,T ≤ R/H vertical field diffuses outward before it can be advected inward by… 

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