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New Calculations of Recombination Rates for Cold $^4$He Atoms and Determination of Universal Scaling Functions

J. R. Shepard
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Abstract

Three-body recombination rates for cold $^4$He are calculated with a new method which exploits the simple relationship between the imaginary part of the atom-dimer elastic scattering phase shift and the $S$-matrix for recombination. The elastic phase shifts are computed above breakup threshold by solving a three-body Faddeev equation in momentum space with inputs based on a variety of modern atom-atom potentials. Recombination coefficients for the HFD-B3-FCII potential agree very well with the only previously published results. Since the elastic scattering and recombination processes for $^4$He are governed by "Efimov physics", they depend on universal functions of a scaling variable. The newly computed recombination coefficients for potentials other than HFD-B3-FCII make it possible to determine these universal functions for the first time.

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J. R. Shepard. 2007-05-24. New Calculations of Recombination Rates for Cold $^4$He Atoms and Determination of Universal Scaling Functions. https://doi.org/10.1103/physreva.75.062713

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