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Quantum Dynamics of Ultracold Na + Na_2 collisions

Pavel Soldan·Marko T. Cvitas·Jeremy M. Hutson·Pascal Honvault·Jean-Michel Launay
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Abstract

Ultracold collisions between spin-polarized Na atoms and vibrationally excited Na_2 molecules are investigated theoretically, using both an inelastic formalism (neglecting atom exchange channels) and a reactive formalism (including atom exchange). Calculations are carried out on both pairwise additive and non-additive potential energy surfaces for the quartet electronic state. In both inelastic and reactive calculations, the Wigner threshold laws are followed for energies below 10^{-6} K. It is found that vibrational relaxation processes dominate elastic processes for temperatures below 10^{-3} - 10^{-4} K. For temperatures below 10^{-5} K, the rate coefficients for vibrational relaxation (v = 1 -> 0) from the full calculation are 4.8 x 10^{-11} and 5.2 x 10^{-10} cm^3 s^-1 for the additive and non-additive potentials respectively.

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Pavel Soldan, Marko T. Cvitas, Jeremy M. Hutson, Pascal Honvault, Jean-Michel Launay. 2002-05-03. Quantum Dynamics of Ultracold Na + Na_2 collisions. https://doi.org/10.1103/physrevlett.89.153201

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