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Thermalization of magnetically trapped metastable helium

A. Browaeys·A. Robert·O. Sirjean·J. Poupard·S. Nowak·D. Boiron·C. I. Westbrook·A. Aspect
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Abstract

We have observed thermalization by elastic collisions of magnetically trapped metastable helium atoms. Our method directly samples the reconstruction of a thermal energy distribution after the application of an RF knife. The relaxation time of our sample towards equilibrium gives an elastic collision rate constant close to the unitarity limit.

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A. Browaeys, A. Robert, O. Sirjean, J. Poupard, S. Nowak, D. Boiron, C. I. Westbrook, A. Aspect. 2001-02-21. Thermalization of magnetically trapped metastable helium. https://doi.org/10.1103/physreva.64.034703

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