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Theory of evaporative cooling with energy-dependent elastic scattering cross section and application to metastable helium

Paul J. J. Tol·W. Hogervorst·W. Vassen
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Abstract

The kinetic theory of evaporative cooling developed by Luiten et al. [Phys. Rev. A 53, 381 (1996)] is extended to include the dependence of the elastic scattering cross section on collision energy. We introduce a simple approximation by which the transition range between the low-temperature limit and the unitarity limit is described as well. Applying the modified theory to our measurements on evaporative cooling of metastable helium we find a scattering length |a| = 10(5) nm.

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Paul J. J. Tol, W. Hogervorst, W. Vassen. 2003-12-09. Theory of evaporative cooling with energy-dependent elastic scattering cross section and application to metastable helium. https://doi.org/10.1103/physreva.70.013404

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