A Global Magnetohydrodynamic Simulation of the Origin and Evolution of Magnetic Flux Ropes in the Magnetotail.

• Walker Raymond J.

  Institute of Geophysics and Planetary Physics, University of California

• Ogino Tatsuki

  Solar Terrestrial Environment Laboratory, Nagoya University

Bibliographic Information

Other Title

• Global Magnetohydrodynamic Simulation o

Abstract

We have used a three dimensional global magnetohydrodynamic simulation to model the response of the magnetosphere to an interplanetary magnetic field (IMF) with B_z < 0 and B_y ≠ 0 in order to study the origin and evolution of magnetic flux ropes in the magnetotail. The southward IMF leads to dayside magnetic reconnection followed by reconnection on closed plasma sheet field lines. When there initially was no IMF B_y in the plasma sheet, reconnection led to the formation of a plasmoid composed of a quasi-two dimensional closed magnetic loop structure. When IMF B_y reached the equatorial region the quasi-two dimensional plasmoid became a magnetic flux rope. For IMF B_y ≠ 0 initially in the plasma sheet the reconnection immediately led to the formation of a flux rope structure. The pitch of the flux rope field lines is determined by the amount of B_y. For the case with no initial B_y in the plasma sheet the pitch was relatively large while when B_y ≠ 0 initially the flux rope resembled a flux tube lying across the tail. Flux ropes in the magnetotail consist of closed, open and IMF field lines. The open and IMF field lines in the flux rope become attached to the IMF when closed field lines in the flux rope reconnect with IMF field lines at the flank magnetopause. Flux ropes can move tailward before all of the closed field lines have reconnected. This is primarily caused by the tension on IMF field lines which drape over the flux rope when lobe field lines reconnect. However the tailward velocity is less for flux ropes than for plasmoids because of the connection to the Earth. In the simulation closed flux rope field lines are found over 100R_E down the tail.

Journal

• Journal of geomagnetism and geoelectricity

  Journal of geomagnetism and geoelectricity 48 (5/6), 765-779, 1996

  Society of Geomagnetism and Earth, Planetary and Space Sciences

Keywords

• General Earth and Planetary Sciences
• General Environmental Science

Details

• CRID: 1390282681487248384
• NII Article ID: 130003559426
• NII Article ID: 10002403606
• NII Book ID: AA00698879
• DOI: 10.5636/jgg.48.765
• ISSN: 21855765
• ISSN: 00221392
• NDL BIB ID: 4060371
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I4060371
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed