Electron reacceleration in flares and resulting modifications of the 'standard' Thick Target Model of electron beams
Abstract
A modified Thick Target Model proposed by Brown et al. (2009) and termed the Local Reac-celeration Thick Target Model (LRTTM) offers a possible solution of these CTTM problems by invoking reacceleration of electrons after injection from a coronal primary acceleration region. Various reacceleration processes are possible, including in current sheet cascades but, provided the acceleration rate offsets collisional losses, electron lifetimes and HXR yield are greatly in-creased, so that the necessary beam density is much reduced, as is the HXR source electron anisotropy. The total beam power input required in the LRTTM is, however, no less than in the CTTM and, furthermore it has predominantly to be released in the chromosphere. This, together with the longer range of reaccelerated electrons, may affect the vertical distribution of beam heating with possible consequences for white light flare production and chromospheric explosive evaporation models.
- Publication:
-
38th COSPAR Scientific Assembly
- Pub Date:
- 2010
- Bibcode:
- 2010cosp...38.2976B