Unified fluid-model theory of $\mathbf{E}\times\mathbf{B}$ instabilities in low-ionized collisional plasmas with arbitrarily magnetized multi-species ions

TL;DR

This paper presents a unified linear fluid-model theory for various plasma instabilities in low-ionized, collisional plasmas with multi-species ions, relevant to planetary ionospheres, star atmospheres, and solar chromosphere heating.

Contribution

It introduces a comprehensive linear dispersion relation for collisional plasma instabilities in multi-species ionized plasmas, applicable across different magnetization regimes.

Findings

Derived a general dispersion relation for TFBI.

Analyzed key limiting cases of the theory.

Demonstrated model's applicability for large-scale plasma simulations.

Abstract

This paper develops a unified linear theory of local cross-field plasma instabilities, such as the Farley-Buneman, electron thermal, and ion thermal instabilities, in collisional plasmas with fully or partially unmagnetized multi-species ions. Collisional lasma instabilities in low-ionized, highly dissipative, weakly magnetized plasmas play an important role in the lower Earth's ionosphere and may be of importance in other planet ionospheres, star atmospheres, cometary tails, molecular clouds, accretion disks, etc. In the solar chromosphere, macroscopic effects of collisional plasma instabilities may contribute into significant heating -- an effect originally suggested from spectroscopic observations and relevant modeling. Based on a simplified 5-moment multi-fluid model, the theoretical analysis produces the general linear dispersion relation for the combined Thermal-Farley-Buneman Instability (TFBI). Important limiting cases are analyzed in detail. The analysis demonstrates acceptable applicability of this model for the rocesses under study. Fluid-model simulations usually require much less computer resources than do more accurate kinetic simulations, so that the apparent success of this approach to the linear theory of collisional plasma instabilities makes it possible to investigate the TFBI (along with its possible macroscopic effects) using global fluid codes originally developed for large-scale modeling of the solar and planetary atmospheres.