Anomalous aspects of magnetosheath flow and of the shape and oscillations of the magnetopause during an interval of strongly northward interplanetary magnetic field

Technical Report · Tue Sep 01 04:00:00 EDT 1992

OSTI ID:6306067

Chen, S; Kivelson, M G; Gosling, J T; Walker, R T; Lazarus, A J

On 15 Feb. 1978, the orientation of the interplanetary magnetic field (IMF) remained steadily northward for more than 12 hours. The ISEE 1 and 2 spacecraft were located near apogee on the dawn side flank of the magnetotail. IMP 8 was almost symmetrically located in the magnetosheath on the dusk flank and IMP 7 was upstream in the solar wind. Using plasma and magnetic field data, the authors show the following: (1) the magnetosheath flow speed on the flanks of the magnetotail steadily exceeded the solar wind speed by 20 percent; (2) surface waves with approximately a 5-min period and very non-sinusoidal waveform were persistently present on the dawn magnetopause and waves of similar period were present in the dusk magnetosheath; and (3) the magnetotail ceased to flare at an antisunward distance of 15 R(sub E). They propose that the acceleration of the magnetosheath flow is achieved by magnetic tension in the draped field configuration for northward IMF and that the reduction of tail flaring is consistent with a decreased amount of open magnetic flux and a larger standoff distance of the subsolar magnetopause. Results of a three-dimensional magnetohydrodynamic simulation support this phenomenological model.

• Research Organization: California Univ., Los Angeles, CA (United States)
• OSTI ID: 6306067
• Report Number(s): N-93-25081; NASA-CR--192851; NAS--1.26:192851; CNN: NAG5-1529
• Country of Publication: United States
• Language: English

Related Subjects

661320* -- Auroral
Ionospheric
& Magnetospheric Phenomena-- (1992-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
COMPUTERIZED SIMULATION
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
FLUID MECHANICS
HYDRODYNAMICS
INTERPLANETARY MAGNETIC FIELDS
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
MAGNETOPAUSE
MAGNETOSHEATH
MAGNETOTAIL
MECHANICS
OSCILLATIONS
PLASMA DRIFT
SIMULATION