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Kinetics of the evaporative cooling of an atomic beam

Thierry Lahaye·David Guéry-Odelin
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Abstract

We compare two distincts models of evaporative cooling of a magnetically guided atomic beam: a continuous one, consisting in approximating the atomic distribution function by a truncated equilibrium distribution, and a discrete-step one, in which the evaporation process is described in terms of successive steps consisting in a truncation of the distribution followed by rethermalization. Calculations are performed for the semi-linear potential relevant for experiments. We show that it is possible to map one model onto the other, allowing us to infer, for the discrete-step model, the rethermalization kinetics, which turns out to be strongly dependent upon the shape of the confining potential.

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Thierry Lahaye, David Guéry-Odelin. 2006-01-31. Kinetics of the evaporative cooling of an atomic beam. https://doi.org/10.1103/physreva.73.063622

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