Ar XIII line ratios in solar flares
Abstract
Theoretical ArXIII electron-density-sensitive emission line ratios, derived using electron impact excitation rates interpolated from accurateR-matrix calculations, are presented forR1 =I(242.22 å)/I(236.27 å),R2 =I(210.46 å)/I(236.27 å), andR3 =I(248.68 å)/I(236.27 å). Electron densities deduced from the observed values ofR1,R2, andR3 for solar flares obtained with the NRL S082A slitless spectrograph on boardSkylab are in excellent agreement, and furthermore compare favorably with those determined from line ratios in CaXV, which is formed at a similar electron temperature to that of ArXIII. These results provide experimental support for the accuracy of the atomic data adopted in the analysis, as well as for the techniques used to calculate the line ratios.
- Publication:
-
Solar Physics
- Pub Date:
- June 1993
- DOI:
- 10.1007/BF00690657
- Bibcode:
- 1993SoPh..145..291K
- Keywords:
-
- Electron Density (Concentration);
- Electron Energy;
- Emission Spectra;
- Solar Flares;
- Argon;
- Electron Transitions;
- Spectral Bands;
- Spectroheliographs;
- Solar Physics;
- Flare;
- Excellent Agreement;
- Emission Line;
- Electron Impact;
- Electron Temperature