HR: 08:45h
AN: SP41C-02    [Abstracts]
TI: Stochastic Particle Acceleration in a Self-Consistent Solar Flare Atmosphere
AU: * Miller, J A
EM: MillerJA@UAH.edu
AF: University of Alabama in Huntsville, Department of Physics, Huntsville, AL 35899 United States
AU: Mariska, J T
EM: mariska@nrl.navy.mil
AF: Naval Research Laboratory, Code 7673, Washington, DC 20375-5000 United States
AB: We present results from a unified and self-consistent model of particle acceleration and atmospheric response in impulsive solar flares. In our model, electrons and ions are stochastically energized from thermal to relativistic energies on short timescales by cascading MHD turbulence, which is assumed to have been excited initially in the coronal region of a flare loop during the primary energy release phase. The accelerated particles then propagate to the denser transition region and chromosphere, where they can deposit a large fraction of their energy and drive the formation of a hydrodynamic shock that propagates back into the corona. The density enhancements that accompany this shock in turn modify the particle acceleration processes in the corona by altering (in a spatially-dependent manner) the density and Alfvén speed, and hence the acceleration rates and threshold energies. The two main components of this simulation are the NRL Dynamic Solar Flux Tube Model code and a spatially-dependent quasilinear particle acceleration/wave evolution code. As such, it provides a comprehensive treatment of both macroscopic (chromospheric evaporation) and microscopic (wave-particle interactions) processes. We demonstrate the coupling between acceleration and atmospheric response by presenting simulation results for realistic flare parameters, and show the importance of including the later process in particle acceleration studies. We also show that acceleration by cascading MHD turbulence is able to account for all the major features of flare energetic particles. This work was supported by NASA grant NAG5-12794.
DE: 2159 Plasma waves and turbulence
DE: 7514 Energetic particles (2114)
DE: 7519 Flares
DE: 7843 Numerical simulation studies
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly