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Compressible Sub-Alfvenic MHD turbulence in Low-beta Plasmas

Jungyeon Cho·A. Lazarian
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Abstract

We present a model for compressible sub-Alfvenic isothermal magnetohydrodynamic (MHD) turbulence in low-beta plasmas and numerically test it. We separate MHD fluctuations into 3 distinct families - Alfven, slow, and fast modes. We find that, production of slow and fast modes by Alfvenic turbulence is suppressed. As a result, Alfven modes in compressible regime exhibit scalings and anisotropy similar to those in incompressible regime. Slow modes passively mimic Alfven modes. However, fast modes show isotropy and a scaling similar to acoustic turbulence.

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BibTeXRIS

Jungyeon Cho, A. Lazarian. 2002-05-17. Compressible Sub-Alfvenic MHD turbulence in Low-beta Plasmas. https://doi.org/10.1103/physrevlett.88.245001

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