On the evolution of a magnetic flux rope: Two-dimensional MHD simulation results

Teh Wai Leong, T. K M Nakamura, R. Nakamura, W. Baumjohann, Mardina Abdullah

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We use the time-dependent, two-dimensional (2-D), ideal MHD equations to simulate and investigate the evolution of magnetic field and plasma profiles of the typical (T) and crater (C) magnetic flux ropes (FRs). The T-FR has a magnetic pressure peak at the center of the flux rope, while the C-FR has a local dip instead. The simulation starts with a 2-D magnetic flux rope in magnetohydrostatic equilibrium, where pressure gradient forces are balanced by Lorentz forces. The magnetic field and plasma pressure profiles for the initial flux rope are derived from the analytical solutions by Zhang et al. (2010). The initial flux rope starts to evolve when the force balance is broken by imposing pressure or magnetic field perturbations onto the equilibrium system. The pressure perturbations are produced by increasing/decreasing the internal plasma pressure of the flux rope, while the magnetic field perturbations are produced by increasing/decreasing the transverse magnetic fields across the flux rope. We conclude that a T-FR can be evolved into a C-FR and vice versa, if the perturbation strength is sufficient, and that the plasma pressure and density in the new equilibrium state could be either increased or decreased for the evolution of C-FR to T-FR and also for the evolution of T-FR to C-FR. Key Points T-FR can be evolved into C-FR and vice versa Initial stage of both T-FR and C-FR can be either a T-like or C-like FR Pressure and density could be increased/decreased during C-to-T and during T-to-C.

Original languageEnglish
Pages (from-to)8547-8558
Number of pages12
JournalJournal of Geophysical Research A: Space Physics
Volume120
Issue number10
DOIs
Publication statusPublished - 1 Oct 2015

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ropes
Magnetic flux
Magnetohydrodynamics
magnetic flux
Fluxes
magnetic field
perturbation
simulation
plasma
magnetic fields
plasma pressure
pressure field
Magnetic fields
pressure gradient
crater
dip
Plasmas
magnetohydrostatics
internal pressure
Lorentz force

Keywords

  • magnetic flux ropes
  • magnetohydrodynamics

ASJC Scopus subject areas

  • Space and Planetary Science
  • Geophysics

Cite this

On the evolution of a magnetic flux rope : Two-dimensional MHD simulation results. / Wai Leong, Teh; Nakamura, T. K M; Nakamura, R.; Baumjohann, W.; Abdullah, Mardina.

In: Journal of Geophysical Research A: Space Physics, Vol. 120, No. 10, 01.10.2015, p. 8547-8558.

Research output: Contribution to journalArticle

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