Pressure tensor in the presence of velocity shear: stationary solutions and self-consistent equilibria

TL;DR

This paper derives analytical plasma equilibria with asymmetric pressure tensors in sheared flows, enhancing understanding of anisotropic, non-gyrotropic states in collisionless plasmas relevant for space and laboratory environments.

Contribution

It introduces new self-consistent solutions for the pressure tensor in sheared magnetized plasmas, accounting for asymmetries and non-gyrotropic effects.

Findings

Derived analytical equilibria with pressure tensor asymmetry

Revealed conditions for persistent anisotropic states in sheared flows

Applicable to fluid models with full pressure tensor dynamics

Abstract

Observations and numerical simulations of laboratory and space plasmas in almost collisionless regimes reveal anisotropic and non-gyrotropic particle distribution functions. We investigate how such states can persist in the presence of a sheared flow. We focus our attention on the pressure tensor equation in a magnetized plasma and derive analytical self-consistent plasma equilibria which exhibit a novel asymmetry with respect to the magnetic field direction. These results are relevant for investigating, within fluid models that retain the full pressure tensor dynamics, plasma configurations where a background shear flow is present.