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arXiv:1801.02947 · Physical Review A

Two-body loss rates for reactive collisions of cold atoms

Christian Cop, R. Walser

Published Jan 12, 2018• 5 citations
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Abstract

We present an effective two-channel model for reactive collisions of cold atoms. It augments elastic molecular channels with an irreversible, inelastic loss channel. Scattering is studied with the distorted-wave Born approximation and yields general expressions for angular momentum resolved cross sections as well as two-body loss rates. Explicit expressions are obtained for piecewise constant potentials. A pole expansion reveals simple universal shape functions for cross sections and two-body loss rates in agreement with the Wigner threshold laws. This is applied to collisions of metastable $^{20}\mathrm{Ne}$ and $^{21}\mathrm{Ne}$ atoms, which decay primarily through exothermic Penning or associative ionization processes. From a numerical solution of the multichannel Schr\"odinger equation using the best currently available molecular potentials, we have obtained synthetic scattering data. Using the two-body loss shape functions derived in this paper, we can match these scattering data very well.

DOI
10.1103/physreva.97.012704

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