Two-body loss rates for reactive collisions of cold atoms

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 piece-wise 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 ${}^{20}$Ne -- ${}^{21}$Ne atoms, which decay primarily through exothermic Penning-, or Associative- ionization processes. From a numerical solution of the multichannel Schrödinger 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.

12 pages, 11 color figures, to be published in Phys. Rev. A in 2018

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Cited by in corpus (2)

• Imaging recoil ions from optical collisions between ultracold, metastable neon isotopes
• Coherent dynamics in a five-level atomic system