Particle Acceleration in Fragmenting Periodic Reconnecting Current Sheets in Solar Flares
Abstract
Proton and electron acceleration in a fragmenting periodic current sheet (CS) is investigated, based on the forced magnetic reconnection scenario. The aim is to understand the role of CS fragmentation in high-energy beam generation in solar flares. We combine magnetohydrodynamics and test-particle models to consider particle trajectories consistent with a time-dependent reconnection model. It is shown that accelerated particles in such a model form two distinct populations. Protons and electrons moving in open magnetic field have energy spectra that are a combination of the initial Maxwellian distribution and a power-law high-energy (E>20 keV) part. The second population contains particles moving in a closed magnetic field around O-points. These particles move predominantly along the guiding field and their energies fall within quite a narrow range between ~1 MeV and ~10 MeV. It is also found that particles moving in an open magnetic field have a considerably wider pitch-angle distribution.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2010
- DOI:
- 10.1088/0004-637X/720/2/1603
- Bibcode:
- 2010ApJ...720.1603G
- Keywords:
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- acceleration of particles;
- magnetic reconnection;
- Sun: flares