# The turbulent magnetic prandtl number of mhd turbulence in disks

@article{Guan2009TheTM, title={The turbulent magnetic prandtl number of mhd turbulence in disks}, author={Xiaoyue Guan and Charles F. Gammie}, journal={The Astrophysical Journal}, year={2009}, volume={697}, pages={1901-1906} }

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…

## 89 Citations

LARGE-SCALE MAGNETIC FIELD IN ACCRETION DISKS AND RELATIVISTIC POYNTING-FLUX JETS

- Physics
- 2012

In earlier works we pointed out that the disk's surface layers are non-turbulent and thus highly conducting (or non-diffusive) because of hydrodynamic and/or magnetorotational (MRI) instabilities are…

Scaling of Turbulent Viscosity and Resistivity: Extracting a Scale-dependent Turbulent Magnetic Prandtl Number

- Physics
- 2021

Turbulent viscosity ν t and resistivity η t are perhaps the simplest models for turbulent transport of angular momentum and magnetic fields, respectively. The associated turbulent magnetic Prandtl…

Turbulent magnetic Prandtl number in kinematic magnetohydrodynamic turbulence: two-loop approximation.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2011

The turbulent magnetic Prandtl number in the framework of the kinematic magnetohydrodynamic (MHD) turbulence, where the magnetic field behaves as a passive vector field advected by the stochastic…

VERTICAL STRUCTURE OF STATIONARY ACCRETION DISKS WITH A LARGE-SCALE MAGNETIC FIELD

- Physics
- 2012

In earlier works we pointed out that the disk's surface layers are non-turbulent and thus highly conducting (or non-diffusive) because the hydrodynamic and/or magnetorotational instabilities are…

Turbulent resistivity driven by the magnetorotational instability

- Physics
- 2009

Aims. We measure the turbulent resistivity in the nonlinear regime of the MRI, and evaluate the turbulent magnetic Prandtl number. Methods. We perform a set of numerical simulations with the Eulerian…

Turbulent resistivity evaluation in MRI generated turbulence

- Physics
- 2009

(abriged) MRI turbulence is a leading mechanism for the generation of an efficient turbulent transport of angular momentum in an accretion disk through a turbulent viscosity effect. It is believed…

Angular momentum transport in thin magnetically arrested discs

- Physics
- 2018

In accretion disks with large-scale ordered magnetic fields, the magnetorotational instability (MRI) is marginally suppressed, so other processes may drive angular momentum transport leading to…

Quantifying the effect of turbulent magnetic diffusion on the growth rate of the magneto−rotational instability

- Physics
- 2014

Context. In astrophysics, turbulent diffusion is often used in place of microphysical diffusion to avoid resolving the small scales. However, we expect this approach to break down when time and…

Global MHD Simulations of Accretion Disks in Cataclysmic Variables (CVs): II The Relative Importance of MRI and Spiral Shocks

- Physics
- 2017

We perform global three-dimensional MHD simulations of unstratified accretion disks in cataclysmic variables (CVs). By including mass inflow via an accretion stream, we are able to evolve the disk to…

Turbulent magnetic Prandtl number in helical kinematic magnetohydrodynamic turbulence: two-loop renormalization group result.

- PhysicsPhysical review. E, Statistical, nonlinear, and soft matter physics
- 2013

It is shown that the turbulent PrandTL number and the turbulent magnetic Prandtl number are essentially different when one considers the spatial parity violation, which means that the properties of the diffusion processes in the turbulent systems with a given symmetry breaking can considerably depend on the internal tensor structure of advected quantities.

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