English

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

Solar and Stellar Astrophysics 2018-02-28 v2 Instrumentation and Methods for Astrophysics Atomic Physics

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.

Keywords

Cite

@article{arxiv.1712.01166,
  title  = {Excitation and charge transfer in low-energy hydrogen atom collisions with neutral oxygen},
  author = {P. S. Barklem},
  journal= {arXiv preprint arXiv:1712.01166},
  year   = {2018}
}

Comments

Accepted for A&A. Data will be made available at CDS. Is available here: https://github.com/barklem/public-data. Replaced version corrects url and adds it to the paper