Electron capture by oxygen ions due to collisions with neutral hydrogen,
For most astrophysical applications, the important quantity is the
rate coefficient. Rate coefficients for reactions (1) and
(2) have been calculated by Field & Steigman ([1971])
for
T = 10 - 10000 K and by Chambaud et al. ([1980]) for T = 10 - 1000 K.
Kimura et al. ([1997]) computed rate coefficients for
reaction (2) for T = 10000 - 200000 K. The
results of Chambaud et al. ([1980]), which are
confirmed by the drift-tube measurements of reaction (2) by
Federer et al. ([1984])
for
K, are in significant
disagreement with Field & Steigman ([1971]).
In an attempt to resolve these discrepancies, we have combined new theoretical calculations, using four different approaches applicable in different energy regimes, with previous experimental and theoretical results, to deduce accurate charge transfer cross sections and rate coefficients for processes (1) and (2). Brief descriptions of the scattering theories are given in Sect. 2. New results and comparison with previous data are presented in Sect. 3 with the cross sections given over the very large energy range, 0.1 meV/u - 10 MeV/u, the higher energies being of relevance to ion precipitation into the Jovian atmosphere. This and other applications of the results to astrophysical and atmospheric environments are discussed in Sect. 4.
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