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Structure Function Scaling in Compressible Super-Alfvenic MHD Turbulence

Paolo Padoan·Raul Jimenez·Aake Nordlund·Stanislav Boldyrev
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Abstract

Supersonic turbulent flows of magnetized gas are believed to play an important role in the dynamics of star-forming clouds in galaxies. Understanding statistical properties of such flows is crucial for developing a theory of star formation. In this letter we propose a unified approach for obtaining the velocity scaling in compressible and super--Alfvénic turbulence, valid for arbitrary sonic Mach number, \ms. We demonstrate with numerical simulations that the scaling can be described with the She--Lévêque formalism, where only one parameter, interpreted as the Hausdorff dimension of the most intense dissipative structures, needs to be varied as a function of \ms. Our results thus provide a method for obtaining the velocity scaling in interstellar clouds once their Mach numbers have been inferred from observations.

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Paolo Padoan, Raul Jimenez, Aake Nordlund, Stanislav Boldyrev. 2004-05-31. Structure Function Scaling in Compressible Super-Alfvenic MHD Turbulence. https://doi.org/10.1103/physrevlett.92.191102

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