Effective Viscosity, Resistivity, and Reynolds Number in Weakly Collisional Plasma Turbulence

Yan Yang; William H. Matthaeus; Sean Oughton; Riddhi Bandyopadhyay; Francesco Pecora; Tulasi N. Parashar; Vadim Roytershteyn; Alexandros Chasapis; Michael A. Shay

arXiv · 2309.02663

Effective Viscosity, Resistivity, and Reynolds Number in Weakly Collisional Plasma Turbulence

Yan Yang·William H. Matthaeus·Sean Oughton·Riddhi Bandyopadhyay·Francesco Pecora·Tulasi N. Parashar·Vadim Roytershteyn·Alexandros Chasapis·Michael A. Shay

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Abstract

We examine dissipation and energy conversion in weakly collisional plasma turbulence, employing in situ observations from the Magnetospheric Multiscale (MMS) mission and kinetic Particle-in-Cell (PIC) simulations of proton-electron plasma. A previous result indicated the presence of viscous-like and resistive-like scaling of average energy conversion rates -- analogous to scalings characteristic of collisional systems. This allows for extraction of collisional-like coefficients of effective viscosity and resistivity, and thus also determination of effective Reynolds numbers based on these coefficients. The effective Reynolds number, as a measure of the available bandwidth for turbulence to populate various scales, links macro turbulence properties with kinetic plasma properties in a novel way.

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Yan Yang, William H. Matthaeus, Sean Oughton, Riddhi Bandyopadhyay, Francesco Pecora, Tulasi N. Parashar, Vadim Roytershteyn, Alexandros Chasapis, Michael A. Shay. 2023-09-06. Effective Viscosity, Resistivity, and Reynolds Number in Weakly Collisional Plasma Turbulence. https://arxiv.org/abs/2309.02663

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