Solar Physics

, Volume 145, Issue 2, pp 291–296 | Cite as

Ar XIII line ratios in solar flares

  • F. P. Keenan
  • E. S. Conlon
  • V. J. Foster
  • K. M. Aggarwal
  • K. G. Widing


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.


Flare Excellent Agreement Emission Line Electron Impact Electron Temperature 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 1993

Authors and Affiliations

  • F. P. Keenan
    • 1
  • E. S. Conlon
    • 1
  • V. J. Foster
    • 1
  • K. M. Aggarwal
    • 2
  • K. G. Widing
    • 3
  1. 1.Department of Pure and Applied PhysicsThe Queen's University of BelfastBelfastN. Ireland
  2. 2.Department of Physics and AstrophysicsThe University of DelhiDelhiIndia
  3. 3.E.O. Hulburt Center for Space ResearchNaval Research LaboratoryWashingtonUSA

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