Abstract
Flare-associated soft X-ray bursts (8–12 Å) are examined for 283 events observed by OSO-III. These bursts are shown to be predominantly thermal in nature. Their time-profiles are roughly similar to those of the associated Hα flares, although the X-ray burst begins about two minutes earlier, on the average. The strength of the soft X-ray burst is directly related to the area and brilliance of the flare, the age and ‘flare-richness’ of the associated plage, and the general level of solar activity at the time of the burst. The peak enhancements in the soft X-ray and Hα emission rates during flares are of the same order of magnitude, as are the total flare energies radiated at these wavelengths. We estimate that soft X-radiation accounts for up to 10% of a flare's total electromagnetic emission.
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NRC/NAS Resident Research Associate.
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Thomas, R.J., Teske, R.G. Solar soft X-rays and solar activity. Sol Phys 16, 431–453 (1971). https://doi.org/10.1007/BF00162486
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DOI: https://doi.org/10.1007/BF00162486