| Autor: |
David L. Cooper, M. J. Raković, B Zygelman, J. G. Wang, Phillip C. Stancil, W Fritsch, A. R. Turner, David R. Schultz |
| Rok vydání: |
2002 |
| Předmět: |
|
| Zdroj: |
Journal of Physics B: Atomic, Molecular and Optical Physics. 35:3137-3156 |
| ISSN: |
0953-4075 |
| Popis: |
Charge transfer due to collisions of ground-state S4+(3s2?1S) ions with helium is investigated for energies between?0.1?meV?u-1 and 10?MeV?u-1. Total and state-selective single electron capture (SEC) cross sections and rate coefficients are obtained utilizing the quantum mechanical molecular-orbital close-coupling (MOCC), atomic-orbital close-coupling (AOCC), classical trajectory Monte Carlo (CTMC) and continuum distorted wave methods. The MOCC calculations utilize ab initio adiabatic potentials and nonadiabatic radial coupling matrix elements obtained with the spin-coupled valence-bond approach. Previous data are limited to a calculation of the total SEC rate coefficient using the Landau-Zener model that is, in comparison to the results presented here, three orders of magnitude smaller. The MOCC SEC cross sections at low energy reveal a multichannel interference effect. True double capture is also investigated with the AOCC and CTMC approaches while autoionizing double capture and transfer ionization (TI) is explored with CTMC. SEC is found to be the dominant process except for E>200?keV?u-1 when TI becomes the primary capture channel. Astrophysical implications are briefly discussed. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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