ISEE 3 observations of plasmoids with flux rope magnectic topologies

Journal Article · Tue Aug 01 04:00:00 EDT 1995 · Geophysical Research Letters

DOI:https://doi.org/10.1029/95GL01977· OSTI ID:160058

Salvin, J A; Owen, C J; Kuznetsova, M M; Hesse, M

This paper reports new evidence for the existence of plasmoids with force-free flux rope magnetic topologies. Motivated by the fact that force-free magnetic flux ropes have intense axial fields at their centers, the ISEE 3 observations have been searched for plasma sheet intervals in which the magnetic field intensity exceeds that in the lobes by {>=}10% for a minute or longer. A total of 39 {open_quotes}high field regions{close_quotes} were found which met this simple criterion. Further examination showed that they nearly always correspond to the core regions of plasmoids; i.e., intervals of bipolar {Beta}{sub z} with durations of minutes, fast tailward flows and clear substorm associations. A new, more realistic plasmoid magnetic field model which represents the core region as a non-linear force-free flux rope was developed and validated using these events. Finally, observations suggesting that plasmoids evolve toward quasi-force-free flux rope configurations as they move down the tail are presented. 21 refs., 4 figs.

• OSTI ID: 160058
• Journal Information: Geophysical Research Letters, Journal Name: Geophysical Research Letters Journal Issue: 15 Vol. 22; ISSN GPRLAJ; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
FORCE-FREE MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETOTAIL
PLASMA SHEET
PLASMOIDS