The Observed Characteristics of Flare Energy Release. II. High-Speed Soft X-Ray Fronts
Abstract
Flare-associated large-scale brightenings of magnetic loop structures have recently been shown to be related to the propagation of soft X-ray fronts, moving at speeds of the order of 1000 km/s. These are also linked with the brightening of remote H-alpha patches and, in many cases, with type II or U radio emission. A detailed study of the best example found in the Solar Maximum Mission's Hard X-ray Imaging Spectrometer data was performed and with the help of numerical simulations and additional information provided by H-alpha records, it is shown that all together the three energy transport processes proposed by previous authors, namely high-energy particles, conduction fronts, and shocks, play significant roles in the redistribution of flare energy within the loops. The observable evidence of thermal flux limitation and the implication of these and previous results on the efficiency ratio between thermal and nonthermal processes in flares are discussed. Finally, these results are placed under the perspective of the interacting loop model of flares discussed in previous papers, to show that only about 10 percent of the total energy conversion occurs at the interface between loops. The bulk of the flare energy seems to be released internally within one of the bipolar loop structures.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- March 1988
- DOI:
- 10.1086/166107
- Bibcode:
- 1988ApJ...326..451M
- Keywords:
-
- Solar Flares;
- Solar Magnetic Field;
- Solar X-Rays;
- H Alpha Line;
- Light Curve;
- Solar Maximum Mission;
- Solar Physics;
- HYDROMAGNETICS;
- SUN: FLARES;
- SUN: X-RAYS