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arXiv · 0706.2003

Numerical Measurements of the Spectrum in Magnetohydrodynamic Turbulence

Joanne Mason·Fausto Cattaneo·Stanislav Boldyrev
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Abstract

We report the results of an extensive set of direct numerical simulations of forced, incompressible, magnetohydrodynamic turbulence with a strong guide field. The aim is to resolve the controversy regarding the power law exponent (α, say) of the field perpendicular energy spectrum E(k_\perp) \propto k_\perp ^ α. The two main theoretical predictions, α=-3/2 and α=-5/3, have both received some support from numerical simulations carried out by different groups. Our simulations have a resolution of 512^3 mesh points, a strong guide field, an anisotropic simulation domain, and implement a broad range of large-scale forcing routines, including those previously reported in the literature. Our findings indicate that the spectrum of well developed, strong incompressible MHD turbulence with a strong guide field is E(k_{\perp})\propto k_{\perp}^{-3/2}.

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Joanne Mason, Fausto Cattaneo, Stanislav Boldyrev. 2007-06-13. Numerical Measurements of the Spectrum in Magnetohydrodynamic Turbulence. https://doi.org/10.1103/physreve.77.036403

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