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Plasma turbulence in the equatorial electrojet: A two-dimensional Hamiltonian fluid model

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 نشر من قبل Philip Morrison
 تاريخ النشر 2017
  مجال البحث فيزياء
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A nonlinear unified fluid model that describes the Equatorial Electrojet, including the Farley-Buneman and gradient-drift plasma instabilities, is defined and shown to be a noncanonical Hamiltonian system. Two geometric constants of motion for the model are obtained and shown to be Casimir invariants. A reformulation of the model shows the roles of the density-gradient scale-length ($L_n$) and the cross-field drift-velocity (${upsilon}_E$) in controlling the dynamics of unstable modes in the growing, transition, and saturation phases of a simulation.



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