The current foci of my research are the kinetic physics of magnetic reconnection, and its broader relation to plasma physics and nonlinear dynamics. Magnetic reconnection is one of the most important energy conversion and transport processes in space plasmas. Among other effects, reconnection enables the entry of solar wind plasmas into Earth’s magnetosphere and the dissipation of magnetic energy. In the solar atmosphere, magnetic reconnection allows topological changes of large-scale magnetic fields, which release magnetic energy to heat solar flares and drive coronal mass ejections. Magnetic reconnection has also been suggested to play a key role in heating the solar corona, and is known to cause sawtooth crashes in fusion devices. For astrophysical systems, the last decade has seen a dramatic surge of interest in the potential role of magnetic reconnection in stellar flares, super-flares in the Crab Nebula, accretion disks and jets emanating from rotating black holes.
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Oppositely directed in-plane magnetic fields are separated by an intense thin out-of-plane current sheet at the kinetic-scale, where the plasma is not frozen-in (i.e., moving together) with magnetic field lines. Magnetic field lines can break and rejoin to different field lines at this so called diffusion region, which includes the topologically important point called the x-line. The reconnected magnetic field has strong curvature, and thus strong magnetic tension, which acts to shoot out plasma and form outflow jets in the ±x-direction. These jets reach the Alfvén speed (VA). To maintain pressure balance, inflowing plasma with speed Vin from the ±z-direction brings more magnetic flux into the x-line, which drives further reconnection. This last step closes the dynamical loop; thus magnetic reconnection is self-driven
Numerical Simulations of Magnetic Reconnection
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Theoretical Modeling of Magnetic Reconnection
In-situ Satellite Observation of Magnetic Reconnection
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observation
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