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arXiv · 0805.4176

Nonlinear structure in a current-carrying collisional dusty plasma

F. Haas·P. K. Shukla
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Abstract

A perpendicular ion drift is investigated as a mechanism for the generation of magnetic field structures in a highly collisional dusty plasma. The basic dissipation mechanism is assumed to be the dust-neutrals momentum exchange, so that plasmas with a small ionization fraction are natural candidates for experiments. The model reduces to a nonlinear partial differential equation for the vector potential. The conditions for linear instability are determined. The stationary states are periodic arrangements for the magnetic field, described by a Lienard equation. The fully depleted (ion-dust) case is also considered in detail. Applications to planetary rings, comets and dust acoustic instability experiments are analyzed. A necessary condition for the validity of the model is a sufficiently slow time-scale of the generated magnetic fields.

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F. Haas, P. K. Shukla. 2008-05-27. Nonlinear structure in a current-carrying collisional dusty plasma. https://doi.org/10.1063/1.2982494

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