Modelling Of Helium Spectrum In Solar Prominences
Abstract
We present NLTE calculations for the neutral and ionized Helium spectrum in quiescent solar prominences. The Hydrogen and Helium atoms are multi-level model atoms, including for Helium the three stages of ionization. Departures from LTE are allowed for each level. We investigate the formation of lines and continuum within the frame of one-dimensional, isothermal and isobaric static slab models. The numerical code used for these calculations allows also the study of Partial Redistribution effects for several lines. The computation results are compared first with former works to see the improvements in the numerical and theoretical treatment, and then with SOHO observations of quiescent prominences at helium wavelengths. A study of the prominence plasma parameters thus can be made.
- Publication:
-
8th SOHO Workshop: Plasma Dynamics and Diagnostics in the Solar Transition Region and Corona
- Pub Date:
- October 1999
- Bibcode:
- 1999ESASP.446..399L