FRONTIERS IN COMPUTATIONAL ASTROPHYSICS

Particle and Flames in Radiative and Magnetic Flows

October 11-15, 2010
Lyon, France

Contribution of Sebastien Fromang

Title

High resolution local simulations of MHD turbulence induced by the magnetorotational instability

Topics

"Stellar structure and evolution"

Keywords

accretion disks - MHD turbulence - Methods

Abstract

MHD turbulence powered by the magnetorotational instability is believed to be the main physical mechanism responsible for angular momentum transport in accretion disks. In the last few years, numerous numerical simulations have shown that its saturation amplitude is largely determined by small scale dissipation coefficients, regardless of the magnetic field geometry. So far, there has been no evidence for an asymptotic regime in which MHD turbulence efficiency becomes independent of these coefficients. In this talk, I will present the first indications for such a decoupling using the results of high resolution numerical simulations performed with a variety of codes and field configurations. Statistical properties of the turbulence (power spectra, transfer functions) will be used to characterize its properties.

Talk