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Recombination

Radiative and dielectronic recombination rates to all spectroscopic levels are calculated from the photoionization cross sections using the Milne relation. We include both spontaneous and stimulated recombination caused by the illuminating radiation. Stimulated recombination by the locally emitted radiation is not treated explicitly, although its effect is taken into account in an approximate way by suppressing a fraction of the spontaneous recombinations using the escape probability described earlier in this section. Recombination onto the superlevels is calculated in order to account for the difference between the sum over all spectroscopic levels and the total ion recombination as given by Nahar and coworkers ([Nahar 1999], [Nahar 2000]) where available and [Aldrovandi and Pequignot 1973] for species other than iron ions and ions in the H and He isoelectronic sequences. For iron we use total rates from [Arnaud and Raymond 1992]. For H and He-like ions the total recombination rates were calculated by [Bautista et al. 1998] and [Bautista and Kallman 2000].



Tim Kallman 2014-09-12