Non-equilibrium two-fluid plasmas can generate magnetic fields and flows simultaneously

TL;DR

This paper presents an analytical solution demonstrating how non-equilibrium two-fluid plasmas can simultaneously generate magnetic fields and plasma flows through baroclinic effects, challenging simplified models like EMHD.

Contribution

It introduces a new analytical model for two-fluid plasmas that accounts for ion dynamics and explains simultaneous magnetic field and flow generation.

Findings

Baroclinic vectors can generate magnetic fields and flows.

The model's magnetic field estimates align with experimental data.

EMHD model is shown to be inconsistent for this phenomenon.

Abstract

A new analytical solution of the set of highly nonlinear two-fluid equations is presented to explain the mechanism for the generation of "seed" magnetic field and plasma flow by assuming the density n to have a profile like an exponential in xy-plane and temperature profiles of electrons (ions) to be linear in yz-plane. {It is shown that the baroclinic vectors - $\nabla\Psi\times\nabla T_{j}$ (where $\Psi = ln\bar{n}, \bar{n}$ is normalized density, and $T_{j}$ denote the temperatures of electrons and ions for j = e, i) can generate not only the magnetic field but the plasma flow as well.} It is also pointed out that the electron magnetohydrodynamics (EMHD) model has inconsistencies because it does not take into account the ion dynamics while the magnetic field is produced on slow time scale. The estimate of the magnitude of the magnetic field in a classical laser plasma using this model is in agreement with the experimental observations.