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arXiv · 1103.5372

Global limits on kinetic Alfvénon speed in quasineutral plasmas

M. Akbari-Moghanjoughi
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Abstract

Large amplitude kinetic Alfvénon (exact Alfvén soliton) matching condition is investigated in quasineutral electron-ion and electron-positron-ion plasmas immersed in a uniform magnetic field. Using the standard pseudopotential method, the magnetohydrodynamics (MHD) equations are exactly solved and a global allowed matching condition for propagation of kinetic solitary waves is derived. It is remarked that, depending on the plasma parameters, the kinetic solitons can be sub- or super-Alfvénic, in general. It is further revealed that, either upper or lower soliton speed-limit is independent of fractional plasma parameters. Furthermore, the soliton propagation angle with respect to that of the uniform magnetic field is found to play a fundamental role in controlling the soliton matching speed-range.

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M. Akbari-Moghanjoughi. 2011-03-28. Global limits on kinetic Alfvénon speed in quasineutral plasmas. https://doi.org/10.1063/1.3581075

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