Sheared-flow Generalization of the Harris Sheet
نویسنده
چکیده
A novel, exact class of solutions to the Vlasov–Maxwell system, with self– generated magnetic fields and nonuniform plasma flows, are constructed. It is shown that a gyrotropic distribution function (independent of gyrophase) does not allow equilibrium shear flow; introduction of agyrotropy is essential for the maintenance of spatially nonuniform velocity fields. The new self–consistent sheared–flow solutions include the shearless Harris Sheet [E.G. Harris, Nuovo Cimento 23, 117 (1962)] solution as a special case. These equilibria are likely to be relevant to a variety of astrophysical flows (most natural flows are sheared) and to a better understanding of the laboratory phenomena observed, for example, in the device MRX (Magnetic Reconnection Experiment, M. Yamada, H. Ji, S. Hsu, T. Carter, R. Kulsrud, N. Bretz, F. Jodes, Y. Ono, and F. Perkins, Phys. Plasma 4, 1936 (1997)) designed to study magnetic reconnection. Typeset using REVTEX 1
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