Correlation functions and pressure of non-isothermal plasma

TL;DR

This paper derives correlation functions for non-isothermal plasma, revealing how weakly damping ionic sound waves influence pressure and correlation behavior, especially when electron temperature greatly exceeds ion temperature.

Contribution

It provides new expressions for correlation functions in non-isothermal plasma and shows how ionic sound waves affect pressure, differing from equilibrium cases.

Findings

Correlation functions derived for non-isothermal plasma.

Presence of ionic sound waves alters pressure sign.

Strong correlations occur when electron temperature is much higher than ion temperature.

Abstract

Expressions for correlation functions of classical non-isothermal two-component plasma are derived. In the limiting case of $\Theta_e\gg\Theta_i$ strong correlations arise due to the existence of weakly damping waves (ionic sound), whose phase velocity is between the thermal velocities of particles, $u_e\gg\omega/k\gg u_i$. Owing to these correlations, the additional term in the expression for pressure due to the Coulomb interaction changes its sign as compared to the case of thermodynamic equilibrium where such waves do not exist.