Summary
From the theoretical investigation ofLetfus andApostolov (1974) it follows that under flare conditions the intensive X-ray emission lines in the 1–8 Å range have an insignificant contribution to the ionization state of the lower ionosphere in comparison with the enhanced emission of the continuum. This result is experimentally confirmed by direct comparison of the intensity variations of the emission line 1.87 Å (Fe XXV) during the solar flare of 25 July 1967 measured onboard of the OSO III satellite with simultaneous ground observations of the ionization state variations of the lower ionosphere made by the A3 method.
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References
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Letfus, V., Apostolov, E.M. & Nestorov, G.T. Experimental examination of the possible influence of the 1.87 Å line emission on the fine structure of the lower ionosphere ionization. PAGEOPH 116, 1–7 (1978). https://doi.org/10.1007/BF00878981
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DOI: https://doi.org/10.1007/BF00878981