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Physical Review A

Shape resonances and nonadiabatic dynamics in O(3Pj)+He collisions at cold and ultracold temperatures

Roman V. Krems, A. Dalgarno

Published Jul 2, 2002• 10 citations
Publisher

Abstract

The dynamics of the elastic and inelastic scattering of helium atoms in collisions with oxygen atoms in different fine-structure levels $\mathrm{O}{(}^{3}{P}_{j})$ at cold and ultracold temperatures is investigated using two sets of interaction potentials of the molecule HeO in the ground \ensuremath{\Sigma} and \ensuremath{\Pi} states. Scattering resonances occur in the collisions at low energies. The positions and shapes of the resonance peaks in the inelastic channels do not always mirror those in the elastic channels. The real parts of the scattering lengths are all positive with values in the range 2.5--4.2 \AA{}. The rate coefficients for the quenching of the ${}^{3}{P}_{0}$ and ${}^{3}{P}_{1}$ fine-structure levels decrease almost by one order of magnitude as the temperature decreases from 1 to 0 K and their zero temperature values are, respectively, $3.09\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ and $3.27\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}12}$ ${\mathrm{cm}}^{3}{\mathrm{sec}}^{\ensuremath{-}1}.$

DOI
10.1103/physreva.66.012702

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