Theoretical He I Emissivities in the Case B Approximation
arXiv:astro-ph/0502224 · doi:10.1086/429370
Abstract
We calculate the He I case B recombination cascade spectrum using improved radiative and collisional data. We present new emissivities over a range of electron temperatures and densities. The differences between our results and the current standard are large enough to have a significant effect not only on the interpretation of observed spectra of a wide variety of objects but also on determinations of the primordial helium abundance.
Accepted to ApJL