On the average shape and position of the geomagnetic neutral sheet and its influence on plasma sheet statistical studies

Journal Article · Fri Jul 01 00:00:00 EDT 1988 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA093iA07p07345· OSTI ID:5181816

Dandouras, J ^[1]

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1. CNRS/Toulouse Univ. (France)

A geometric model of the average geomagnetic neutral sheet is presented. The average neutral sheet is best fitted by a smooth warped surface that crosses the solar magnetospheric equatorial plane near the tail flanks and that has no slope discontinuities. The geometry is defined to fit a magnetohydrostatic equilibrium model of the magnetotail, and the values of the parameters are determined by minimizing the Rms deviation from zero of the satellite distance to the model position of the neutral sheet when B{sub X} polarity reversals are observed. The average neutral sheet position given here is optimized for geocentric distances of the order of 20 - 22 R{sub E} (ISEE orbit). Comparison with the Fairfield neutral sheet model, which is optimum for R 30 - 40 R{sub E}, shows the overall geometric stability of the average neutral sheet and its alignment parallel to the solar wind flow. A small flattening that is observed as a function of the increasing geocentric distance is due to the greater magnetopause radius and the reduced influence of the tilted geomagnetic dipole. The model presented here is used to examine the spatial distribution of the particle flux dropouts observed in the plasma sheet, and it is confirmed that in the central magnetotail ({vert bar} Y {vert bar} < 10 R{sub E}) the plasma sheet can be completely pinched during substorms.

• OSTI ID: 5181816
• Journal Information: Journal of Geophysical Research; (United States), Vol. 93:A7; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
PLASMA SHEET
MATHEMATICAL MODELS
COMPARATIVE EVALUATIONS
COORDINATES
ENERGY LOSSES
GEOMAGNETIC FIELD
MAGNETIC BAYS
MAGNETOTAIL
SOLAR WIND
SPATIAL DISTRIBUTION
STATISTICS
DISTRIBUTION
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
EVALUATION
LOSSES
MAGNETIC FIELDS
MATHEMATICS
SOLAR ACTIVITY
640201* - Atmospheric Physics- Auroral
Ionospheric
&amp; Magetospheric Phenomena