Solar flare X-rays, at energies less than 10 keV, are emitted by hot plasmas located in the corona. Three plasma cooling models are examined in detail. The cooling of the electrons by Coulomb collisions with ions at a lower temperature would require the observed material to occupy very large volumes
Enthalpy flux cooling of the solar corona
โ Scribed by Steven G. Wallenhorst
- Publisher
- Springer
- Year
- 1982
- Tongue
- English
- Weight
- 448 KB
- Volume
- 77
- Category
- Article
- ISSN
- 0038-0938
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โฆ Synopsis
The differential emission measure profile for quiet and flaring solar regions is considered, using a model in which the principal downflow of heat is due to the enthalpy of downward-flowing material, rather than conduction. It is found that the emission measure profile for quiet solar regions is matched well by a downward particle number flux which decreases with temperature. This would be expected if this particle flux is due to heated spicular material falling back onto the chromosphere. In flaring regions, however, a particle flux which increases with temperature is required to explain the steep emission measure profile. This could be a result of mass motions downward out of the flaring loops.
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