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arXiv · 1712.01166

Excitation and charge transfer in low-energy hydrogen atom collisions with neutral oxygen

P. S. Barklem
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Abstract

Excitation and charge transfer in low-energy O+H collisions is studied; it is a problem of importance for modelling stellar spectra and obtaining accurate oxygen abundances in late-type stars including the Sun. The collisions have been studied theoretically using a previously presented method based on an asymptotic two-electron linear combination of atomic orbitals (LCAO) model of ionic-covalent interactions in the neutral atom-hydrogen-atom system, together with the multichannel Landau-Zener model. The method has been extended to include configurations involving excited states of hydrogen using an estimate for the two-electron transition coupling, but this extension was found to not lead to any remarkably high rates. Rate coefficients are calculated for temperatures in the range 1000 - 20000 K, and charge transfer and (de)excitation processes involving the first excited S-states, 4s.5So and 4s.3So, are found to have the highest rates.

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P. S. Barklem. 2017-12-04. Excitation and charge transfer in low-energy hydrogen atom collisions with neutral oxygen. https://doi.org/10.1051/0004-6361%2F201731968

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