Aimed at ionization balance and spectral analysis of UV and X-ray sources , we present self-consistent sets of photoionization cross sections , recombination cross sections , and rate coefficients for Li-like O VI and He-like O VII .
Relativistic fine structure is considered through the Breit-Pauli R-matrix ( BPRM ) method in the close coupling approximation , implementing the unified treatment for total electron-ion recombination subsuming both radiative and di-electronic recombination processes .
Self-consistency is ensured by using an identical wavefunction expansion for the inverse processes of photoionization and photo-recombination .
Radiation damping of resonances , important for H-like and He-like core ions , is included .
Compared to previous LS coupling results without radiative decay of low- n n \leq 10 ) resonances , the presents results show significant reduction in O VI recombination rates at high temperatures .
In addition to the total rates , level-specific photoionization cross sections and recombination rates are presented for all fine structure levels n ( \ell SLJ ) up to n \leq 10 , to enable accurate computation of recombination-cascade matrices and spectral formation of prominent UV and X-ray lines such as the 1032,1038 \AA doublet of O VI , and the ‘ triplet ’ forbidden , intercombination , and resonance X-ray lines of O VII at 22.1 , 21.8 , and 21.6 \AA respectively .
Altogether , atomic parameters for 98 levels of O VI and 116 fine structure levels of O VII are theoretically computed .
These data should provide a reasonably complete set of photoionization and recombination rates in collisional or radiative equilibrium .