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Dispersive Waves and Magnetic Reconnection. Alex Flanagan (University of Wisconsin) J. F. Drake (UMD), M. Swisdak (UMD). Magnetic Reconnection?. Magnetic energy converted to kinetic and thermal energy
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Dispersive Waves and Magnetic Reconnection Alex Flanagan (University of Wisconsin) J. F. Drake (UMD), M. Swisdak (UMD)
Magnetic Reconnection? • Magnetic energy converted to kinetic and thermal energy • Occurs in solar corona, magnetosphere, laboratory plasma experiments, and even at edge of solar system
Generalized Ohm’s Law Hall term = whistler waves Electron pressure gradient = kinetic Alfvén waves
Dispersive Waves Dispersive waves: Linear waves:
Sweet-Parker v Fast Reconnection Reconnection Rate Sweet-Parker reconnection: Fast reconnection:
PIC Simulations Kinetic Particle-in-Cell Simulations • Look for: • Size and scaling of dissipation region • Scaling of reconnection rate • Actual reconnection rate of system
Conclusions • Magnetic reconnection is fast in parameter regimes where dispersive waves are possible • There is not a sharp transition between fast and slow reconnection • The parameters we use are similar to those found in solar wind and solar corona
References • Birn, J. et al “Geospace Environmental Modeling (GEM) Magnetic Reconnection Challenge” Journal of Geophysical Research (2001) • Cassak, P. “Catastrophe Model for the Onset of Fast Magnetic Reconnection” Phd Thesis (2006) • Mandt, M. “Transition to Whistler Mediated Magnetic Reconnection” Geophysical Research Letters (1994) • Rodgers, B. “Role of Dispersive Waves in Collisionless Magnetic Reconnection” Physical Review Letters (2001) • Shay, M. “Two-Scale Structure of the Electron Dissipation Region Collisonless Magnetic Reconnection” Physical Review Letters (2007