Title: |
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Analysis of Potassium Abundance in a
Large Number of Flares |
Authors: |
|
J. Sylwester,
B. Sylwester, K. J. H.
Phillips, J. L. Culhane, C. Brown, J. Lang, A. I. Stepanov
|
Abstract: |
|
An initial study of spectra observed in the shortest wavelength channel
(3.40 Å- 3.80 Å) of the RESIK X-ray spectrometer on
CORONAS-F indicates the presence of substantial flare-to-flare variations in
the line-to-continuum ratio of several lines, in particular He-like potassium (K
XVIII) lines, occurring in the range 3.53 Å - 3.57 Å. The observed
variations are larger than those expected from temperature variations. This has
motivated a study of possible variations in the potassium abundance in the
observed spectra. With a new RESIK calibration available, we have obtained
absolute fluxes of the K XVIII resonance line as
well as the continuum and lines observed in other RESIK channels
(3.40 Å - 6.05 Å) for some 1163 intervals observed early in 2003. Analysis of
these observations allowed us to determine the average absolute potassium
abundance for the period studied and investigate the variability of abundance.
The results obtained are presented and discussed. |