Size of the X-ray kernel of the large 1979 August 20 solar flare
Abstract
At the time of the intense class X5 solar flare on August 20, 1979, monochromatic small raster maps near 7 A were recorded of the flaring active region with 20 arc sec resolution (FWHM) by the SOLEX Solar X-ray Spectrometer/Spectroheliograph. From these maps, the spatial extent (FWHM) of the X-ray kernel during the rise of this flare at about 0912 UT was determined to be less than 28 arc sec. The electron density in the hot flare plasma was estimated to be above 10 to the 11th per cu cm. This is the first soft X-ray measurement of the angular size of such an intense flare.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- November 1980
- DOI:
- 10.1086/183385
- Bibcode:
- 1980ApJ...241L.175L
- Keywords:
-
- Solar Flares;
- Solar X-Rays;
- X Ray Spectra;
- Cosmic Plasma;
- Electron Flux Density;
- Solar Corona;
- Spectroheliographs;
- Solar Physics