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Plasma Heating and Particle Acceleration by Turbulence in Solar Flares. Siming Liu Stanford University In collaboration with Vah é Petrosian, Yanwei Jiang, and Wei Liu. Huai Rou Observatory July 9 2005. Outline. Previous Observational Evidence Two New Aspects
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Plasma Heating and Particle Acceleration by Turbulence in Solar Flares Siming Liu Stanford University In collaboration with Vahé Petrosian, Yanwei Jiang, and Wei Liu Huai Rou Observatory July 9 2005
Outline • Previous Observational Evidence • Two New Aspects 3He and heavy ion enrichment Roles of turbulence in the gradual phase • Cascade and Damping of MHD Turbulence • Conclusion
1: Spectral Breaks (Losses vs. Acceleration) 2: LT and FP HXRs (Heating vs. Acceleration) 3: Proton vs. Electron (Injections at Low Energies) 4: 3He Enrichment (Run away Acceleration) Observational Evidence
Two New Aspects The Roles of Turbulence in the Decay Phase 3He and Heavy Ion Enrichment
3Heand Heavy Ion Enrichment: Acceleration by Parallel Propagating Waves
3He and Heavy Ion Enrichment Mason et al. 2004; Reames and Ng 2004
Resonance Condition n=0, v>vA>cs : Transit-time Damping n>0: Cyclotron Resonances Acceleration by parallel propagating waves: n=1
Acceleration of 3He and 4He by Parallel Propagating Waves
Transit-Time Damping? ? Acceleration of 3He and 4He by Parallel Propagating Waves
Acceleration of 3He and 4He by Parallel Propagating Waves
Q/M 1.0 0.5 0.45 Q2/M=1 0.67 Ion Acceleration by Parallel Propagating Waves
? Heavy ion enrichment
The Roles of Turbulence in the Decay Phase Heating & Suppression of Conduction
Equation of Energy Conservation The turbulence can also energize the particles with the acceleration time τac≈ τsc (v/vA)2
? B Measuring the Magnetic Field? τac≈ τsc (v/vA)2; v>vA
Slow Alfvén Fast ~k-5/3 ~k-3/2 ~k-5/3 Cascade and Damping of MHD Waves X X Damping anisotropic (GS) anisotropic (GS) isotropic Cho & Lazarian 2002
Parallel (and perpendicular) waves are not damped Cascade vs. Damping of Turbulence
Conclusion Plasma Wave Turbulence appears to be an important channel for the release of energy during flares & Stochastic Acceleration by it can explain many of the observed flare characteristics