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Theoretical He I Emissivities in the Case B Approximation

R. L. Porter·R. P. Bauman·G. J. Ferland·K. B. MacAdam
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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.

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R. L. Porter, R. P. Bauman, G. J. Ferland, K. B. MacAdam. 2005-02-10. Theoretical He I Emissivities in the Case B Approximation. https://doi.org/10.1086/429370

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