Non-LTE Dynamic Models of Optical Emission During Solar Flares
Abstract
The results from a non-LTE radiative-hydrodynamic model of a flare loop, from its apex in the corona to its footpoints in the photosphere, are presented. The effects of non-thermal heating of the lower solar atmosphere by accelerated electrons during the impulsive phase, and the subsequent effects of soft X-ray irradiation of the chromosphere from the flare-heated transition region and corona during the beginning of the gradual phase are investigated. During the impulsive phase, the models show a significant continuum (or ``white light'') brightening resulting from increased hydrogen recombination radiation in the upper chromosphere at the point where the accelerated electrons deposit the bulk of their energy. Additionally, the models produce a measurable time lag between the brightening of the near wings of H-alpha and the brightening of the Paschen continuum. This work was funded in part by NSF grants AST 96-16886 and AST 94-57455. The computations were partially supported by the National Computational Science Alliance, and utilized the NCSA SGI/CRAY Power Challenge Array.
- Publication:
-
American Astronomical Society Meeting Abstracts #194
- Pub Date:
- May 1999
- Bibcode:
- 1999AAS...194.2206A