Relaxation Processes in Clouds of Trapped Bosons above the Bose-Einstein Condensation Temperature

TL;DR

This paper develops a theoretical framework to describe the damping and relaxation processes in trapped Bose gases above the condensation temperature, linking relaxation times to viscous relaxation estimates and validating with experimental data.

Contribution

It provides a unified theoretical approach to relaxation phenomena in trapped Bose gases, connecting damping and temperature anisotropy relaxation through variational techniques.

Findings

Derived precise expressions for relaxation times

Linked relaxation times to viscous relaxation estimates

Validated theoretical results with experimental data

Abstract

We present a unified account of damping of low-lying collective modes and of relaxation of temperature anisotropies in a trapped Bose gas in the collisionless regime. By means of variational techniques, we show that the relaxation times for the two situations are closely related to the simplest variational estimate of the viscous relaxation time. We derive rather precise theoretical expressions for the characteristic relaxation times, and compare our results with experiment.