ISEE 3 observations during the CDAW 8 intervals: Case studies of the distant geomagnetic tail covering a wide range of geomagnetic activity

Journal Article · Wed Nov 01 04:00:00 EST 1989 · Journal of Geophysical Research; (USA)

DOI:https://doi.org/10.1029/JA094iA11p15189· OSTI ID:6990698

Richardson, I G; Owen, C J; Cowley, S W.H. ^[1]; Galvin, A B ^[2]; Sanderson, T R ^[3]; Scholer, M ^[4]; Slavin, J A ^[5]; Zwickl, R D ^[6]

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1. Blackett Laboratory, Imperial College, London (GB)
2. Department of Physics and Astronomy, University of Maryland, College Park, Maryland (USA)
3. Space Science Department, European Space Agency, European Space Research and Technology Centre, Noordwijk (Netherlands)
4. Max-Planck-Institut feur Physik und Astrophysik, Garching, (Federal Republic of Germany)
5. NASA Goddard Space Flight Center, Greenbelt, Maryland (USA)
6. Los Alamos National Laboratory, Los Alamos, New Mexico (USA)

The data obtained by the ISEE 3 spacecraft during the eight Coordinated Data Analysis Workshop 8 (CDAW 8) intervals provide an excellent opportunity to study the structure and dynamics of the distant geomagnetic tail under a wide range of geomagnetic activity ranging from intervals of magnetic quiet punctuated by isolated substorms to extended intervals of strong disturbance. By examining the properties of the plasma sheet, evidence has been found for the persistence of reconnection in the tail during long intervals of magnetic quiet, with the neutral line lying {approx}100 to 200 R{sub E} or more downtail. The suggestion that the distant tail plasma sheet is populated exclusively by tailward moving closed flux tubes under quiet geomagnetic conditions is therefore not supported. However, a slow plasma sheet regime is also found during such conditions, in which closed flux tubes move slowly tailward in a thick region adjacent to the magnetopause, presumably due to some form of viscous momentum transfer from the magnetosheath. This process does not appear to simultaneously transfer mass into the tail, and there is some indication that the Kelvin-Helmholtz instability is involved. The observations strongly suggest that the closed flux tubes originate from the closed field line plasma sheet region earthward of the neutral line rather than, for example, from the near-Earth low-latitude boundary layer. Plasmoids are observed in the distant tail following disturbance enhancements, the time of their appearance being generally consistent with disconnection from the near-Earth region at the time of the enhancement. Their structure is entirely consistent with the neutral line model.

• OSTI ID: 6990698
• Journal Information: Journal of Geophysical Research; (USA), Journal Name: Journal of Geophysical Research; (USA) Vol. 94:A11; ISSN 0148-0227; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
HELMHOLTZ INSTABILITY
INSTABILITY
MAGNETIC RECONNECTION
MAGNETIC STORMS
MAGNETOTAIL
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES