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.
| Original language | English |
|---|---|
| Pages (from-to) | L73-L75 |
| Journal | Astrophysical Journal |
| Volume | 622 |
| Issue number | 1 II |
| DOIs | |
| State | Published - Mar 20 2005 |
Funding
| Funders | Funder number |
|---|---|
| Directorate for Mathematical and Physical Sciences | 0307720 |
Keywords
- Atomic data
- Atomic processes
- ISM: Atoms -
- ISM: clouds
- Plasmas
ASJC Scopus subject areas
- Astronomy and Astrophysics
- Space and Planetary Science