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arXiv · 2610.35048

Explosive instability, quiet plasma: phase-space cascades, coherent vortices, and transport suppression in a dipole pair plasma

Daniel Kennedy·Gabriel G Plunk
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Abstract

Turbulence in a magnetised dipole pair plasma can transfer electrostatic energy into coherent flows while carrying entropy to small scales. This occurs via a dual cascade in a four-dimensional phase space, whereby advection by the fluctuating electric field nonlinearly phase-mixes the transit-averaged particle motion. Below a critical pressure gradient, zonal bands suppress the kinetic mode, leaving a transport floor. When the fluid mode is unstable, an explosive burst collapses into a zonal condensate on which two vortices "breathe" by reversible energy exchange, without causing net transport.

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Daniel Kennedy, Gabriel G Plunk. 2026-10-26. Explosive instability, quiet plasma: phase-space cascades, coherent vortices, and transport suppression in a dipole pair plasma. https://arxiv.org/abs/2610.35048

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