Numerical linearized MHD model of flapping oscillations

Описание

Тип публикации: статья из журнала

Год издания: 2016

Идентификатор DOI: 10.1063/1.4954388

Ключевые слова: Dispersions, Eigenvalues and eigenfunctions, Linearization, Magnetic fields, Analytical estimates, Current sheets, Dispersion relations, Gradient model, Growth directions, Initial perturbation, Magnetic field components, Mode dispersion, Magnetohydrodynamics

Аннотация: Kink-like magnetotail flapping oscillations in a Harris-like current sheet with earthward growing normal magnetic field component B-z are studied by means of time-dependent 2D linearized MHD numerical simulations. The dispersion relation and two-dimensional eigenfunctions are obtained. The results are compared with analytical estimПоказать полностьюates of the double-gradient model, which are found to be reliable for configurations with small Bz up to values similar to 0.05 of the lobe magnetic field. Coupled with previous results, present simulations confirm that the earthward/tailward growth direction of the Bz component acts as a switch between stable/unstable regimes of the flapping mode, while the mode dispersion curve is the same in both cases. It is confirmed that flapping oscillations may be triggered by a simple Gaussian initial perturbation of the V-z velocity. (C) 2016 Author(s).

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Издание

Журнал: PHYSICS OF PLASMAS

Выпуск журнала: Vol. 23, Is. 6

ISSN журнала: 1070664X

Место издания: MELVILLE

Издатель: AMER INST PHYSICS

Персоны

  • Korovinskiy D.B. (Space Research Institute,Austrian Academy of Sciences)
  • Kiehas S.A. (Space Research Institute,Austrian Academy of Sciences)
  • Ivanov I.B. (Theoretical Physics Division,Petersburg Nuclear Physics Institute)
  • Semenov V.S. (Saint Petersburg State University)
  • Erkaev N.V. (Siberian Federal University)