Dynamics of a classical gas including dissipative and mean field effects

TL;DR

This paper develops an approximate method using a scaling ansatz to analyze the dynamics of a classical gas, including dissipative and mean field effects, focusing on collective oscillations and expansion behavior.

Contribution

It introduces a novel approach to connect relaxation times with damping and expansion, bridging hydrodynamic and collisionless regimes in classical gas dynamics.

Findings

Derived frequencies and damping rates of collective oscillations.

Established a link between relaxation times and expansion dynamics.

Analyzed the crossover between hydrodynamic and collisionless regimes.

Abstract

By means of a scaling ansatz, we investigate an approximated solution of the Boltzmann-Vlasov equation for a classical gas. Within this framework, we derive the frequencies and the damping of the collective oscillations of a harmonically trapped gas and we investigate its expansion after release of the trap. The method is well suited to studying the collisional effects taking place in the system and in particular to discussing the crossover between the hydrodynamic and the collisionless regimes. An explicit link between the relaxation times relevant for the damping of the collective oscillations and for the expansion is established.