S XV Emission-Line Ratios in the Sun
Abstract
Recently calculated electron impact collision rates for S xv are used to derive the electron temperature sensitive emission-line ratio G = x + y + z/w, where z is the forbidden 1s21S-1s2s 3S, w is the resonance 1s2 1S-1s2p 1P and x and y, the intercombination 1s2 1S-1s2p 3P2 and 1s2 1S-1s2p 3P1 transitions, respectively. The value of R = z/x + y, the electron density sensitive ratio, was also calculated in its low-density limit (Ro), and both are plotted as functions of the electron temperature. These are found to be in much better agreement with the observed values of Ro and G obtained by the Flat Crystal Spectrometer on the Solar Maximum Mission satellite for the 1980 November 5 flare than are the previous results of Pradhan and Shull (1981). This improvement provides support for the methods and the atomic data adopted in our calculations.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- May 1988
- DOI:
- 10.1086/166296
- Bibcode:
- 1988ApJ...328..344M
- Keywords:
-
- Abundance;
- Electron Impact;
- Emission Spectra;
- Line Spectra;
- Plasma Interactions;
- Solar Spectra;
- Solar Flares;
- Solar Maximum Mission;
- X Ray Spectra;
- Solar Physics;
- ATOMIC PROCESSES;
- SUN: FLARES;
- SUN: SPECTRA