Abstract
The physical parameters for the kernels of three solar X-ray flare events have been deduced using photographic data from the S-054 X-ray telescope on Skylab as the primary data source and 1–8 and 8–20 Å fluxes from Solrad 9 as the secondary data source. The kernels had diameters of ∼5–7″ and in two cases electron densities at least as high as 3 × 1011 cm−3. The lifetimes of the kernels were 5–10 min. The presence of thermal conduction during the decay phases is used to argue: (1) that kernels are entire, not small portions of, coronal loop structures, and (2) that flare heating must continue during the decay phase.
We suggest a simple geometric model to explain the role of kernels in flares in which kernels are identified with emerging flux regions. The flare is triggered at the neutral sheet between the EFR and a larger loop structure. We associate the X-ray kernels with Hα kernels, which previously associated (incorrectly, we believe) with the nonthermal impulsive phases of flares.
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Most of this work was completed while the author was a Visiting Scientist at the Center for Astrophysics, Cambridge, Massachusetts 02138.
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Kahler, S.W., Petrasso, R.D. & Kane, S.R. The quantitative properties of three soft X-ray flare kernels observed with the AS&E X-ray telescope on Skylab. Sol Phys 50, 179–196 (1976). https://doi.org/10.1007/BF00206200
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DOI: https://doi.org/10.1007/BF00206200