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Spinning up and down a Boltzmann gas

David Guery-Odelin
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Abstract

Using the average method, we derive a close set of linear equations that describes the spinning up of an harmonically trapped gas by a rotating anisotropy. We find explicit expressions for the needed to transfer angular momentum as well as the decay time induced by a static residual anisotropy. These different time scales are compared with the measured nucleation time and lifetime of vortices by the ENS group. We find a good agreement that may emphasize the role played by the non-condensed component in thoses experiments.

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David Guery-Odelin. 2000-03-02. Spinning up and down a Boltzmann gas. https://doi.org/10.1103/physreva.62.033607

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