The Hall dynamo effect and nonlinear mode coupling during sawtooth magnetic reconnection
نویسندگان
چکیده
magnetic reconnection W. X. Ding, D. L. Brower, B. H. Deng, A. F. Almagri, D. Craig, G. Fiksel, V. Mirnov, S. C. Prager, J. S. Sarff, and V. Svidzinski Electrical Engineering Department, University of California at Los Angeles, Los Angeles, California 90095 Center for Magnetic Self-Organization in Laboratory and Astrophysical Plasmas, University of Wisconsin-Madison, Madison, Wisconsin 53706 Department of Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706
منابع مشابه
EX/P5-3 Momentum Transport from Tearing Instability
In the MST reversed field pinch the radial profile of the plasma rotation undergoes a rapid flattening during magnetic reconnection events. The reconnection events are repetitive (occurring as sawtooth crashes) and correspond to bursts of tearing instabilities. The radial transport of toroidal and poloidal momentum occurs faster than can be explained by collisions. We measure the change in mome...
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Current-driven tearing instabilities dominate magnetic relaxation in self-organized high temperature plasmas such as the reversed field pinch (RFP) and spheromak. In the Madison Symmetric Torus (MST) RFP experiments, they are observed in the form of magnetic field, flow velocity, and current density fluctuations that follow a temporally cyclic sawtooth behavior. During a sawtooth crash, a surge...
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The fluctuation-induced Hall electromotive force, [deltaJ x deltaB]/nee, is experimentally measured in the high-temperature interior of a reversed-field pinch plasma by a fast Faraday rotation diagnostic. It is found that the Hall dynamo effect is significant, redistributing (flattening) the equilibrium core current near the resonant surface during a reconnection event. These results imply that...
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