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arXiv · 2409.02769

Magnetic, Kinetic, and Transition Regime: Spatially-Segregated Structure of Compressive MHD Turbulence

Guang-Xing Li·Mengke Zhao
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Abstract

Turbulence is a complex physical process prevalent in modern physics, particularly in ionized environments like interstellar gas, where magnetic fields play a dynamic role. However, the precise influence of magnetic fields in such settings remains unclear. We employ the Alfv\'{e}n Mach number, ${M}_{\mathrm{A}} = \sqrt{E_{\mathrm{k}}/E_{\mathrm{B}}}$, to gauge the magnetic field's significance relative to turbulent motion, uncovering diverse interaction patterns. In the low-${M}_{\mathrm{A}}$ magnetic regime, the field is force-free, yet gas motion does not align with it. At intermediate ${M}_{\mathrm{A}}$ (magnetic-kinetic transition regime), velocity and magnetic fields show peak alignment, likely due to rapid relaxation. In the high-${M}_{\mathrm{A}}$ kinetic regime, both fields are irregular and unaligned. These regimes find observational counterparts in interstellar gas, highlighting the multifaceted nature of MHD turbulence and aiding future astrophysical interpretations.

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Guang-Xing Li, Mengke Zhao. 2024-09-04. Magnetic, Kinetic, and Transition Regime: Spatially-Segregated Structure of Compressive MHD Turbulence. https://arxiv.org/abs/2409.02769

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