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Improved He I Emissivities In The Case B Approximation, R. L. Porter, Gary J. Ferland, P. J. Storey, M. J. Detisch

Physics and Astronomy Faculty Publications

We update our prior work on the case B collisional-recombination spectrum of He i to incorporate ab initio photoionization cross-sections. This large set of accurate, self-consistent cross-sections represents a significant improvement in He i emissivity calculations because it largely obviates the piecemeal nature that has marked all modern works. A second, more recent set of ab initio cross-sections is also available, but we show that those are less consistent with bound-bound transition probabilities than our adopted set. We compare our new effective recombination coefficients with our prior work and our new emissivities with those by other researchers, and we conclude …