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Ionization rates in a Bose-Einstein condensate of metastable Helium

O. Sirjean·S. Seidelin·J. Viana Gomes·D. Boiron·C. I. Westbrook·A. Aspect·G. V. Shlyapnikov
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Abstract

We have studied ionizing collisions in a BEC of He*. Measurements of the ion production rate combined with measurements of the density and number of atoms for the same sample allow us to estimate both the 2 and 3-body contributions to this rate. A comparison with the decay of the number of condensed atoms in our magnetic trap, in the presence of an rf-shield, indicates that ionizing collisions are largely or wholly responsible for the loss. Quantum depletion makes a substantial correction to the 3-body rate constant.

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O. Sirjean, S. Seidelin, J. Viana Gomes, D. Boiron, C. I. Westbrook, A. Aspect, G. V. Shlyapnikov. 2002-08-06. Ionization rates in a Bose-Einstein condensate of metastable Helium. https://doi.org/10.1103/physrevlett.89.220406

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