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).
Журнал: PHYSICS OF PLASMAS
Выпуск журнала: Vol. 23, Is. 6
ISSN журнала: 1070664X
Место издания: MELVILLE
Издатель: AMER INST PHYSICS