Theoretical study on dielectronic recombination ofO6+ions in metastable states

Abstract

A computational scheme, based on the theory of the continuum-bound transitions of Bell and Seaton [J. Phys. B 18, 1589 (1985)] and the close-coupling R-matrix approach, has been developed to treat dielectronic recombination (DR) in high-lying resonance-energy regions. This scheme and our presented numerical method to compute DR in low-lying resonance-energy regions [Phys. Rev. A 62, 022706 (2000)] have been applied together to elucidate the experimental spectra of the DR of ${\mathrm{O}}^{6+}$ ions in the metastable $1s2s{}^{3}S$ and $1s2s{}^{1}S$ states. For comparison, a perturbative theoretical calculation of DR for ${\mathrm{O}}^{6+}$ has also been accompanied. The reasonable representation of the general dielectronic spectral shape is yielded by both our close-coupling and perturbative calculations. However, both the methods do not reproduce the experimental double-peak structure at $\ensuremath{\sim}6$--8 eV. This shows that the further investigation on DR of this kind of ions is required both experimentally and theoretically.