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arXiv · 1705.00749

Nonlinear structures and anomalous transport in partially magnetized $\mathbf{E\times B}$ plasmas

Salomon Janhunen·Andrei Smolyakov·Oleksandr Chapurin·Dmytro Sydorenko·Igor Kaganovich·Yevgeni Raitses
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Abstract

Nonlinear dynamics of the electron-cyclotron instability driven by the electron $\mathbf{E\times B}$ current in crossed electric and magnetic field is studied. In nonlinear regime the instability proceeds by developing a large amplitude coherent wave driven by the energy input from the fundamental cyclotron resonance. Further evolution shows the formation of the long wavelength envelope akin to the modulational instability. Simultaneously, the ion density shows the development of high-k content responsible for wave focusing and sharp peaks on the periodic cnoidal wave structure. It is shown that the anomalous electron transport (along the direction of the applied electric field) is dominated by the long wavelength part of the turbulent spectrum.

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Salomon Janhunen, Andrei Smolyakov, Oleksandr Chapurin, Dmytro Sydorenko, Igor Kaganovich, Yevgeni Raitses. 2017-05-02. Nonlinear structures and anomalous transport in partially magnetized $\mathbf{E\times B}$ plasmas. https://doi.org/10.1063/1.5001206

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