Boundary layer model for magnetospheric substorms. Progress report

Technical Report · Sun Nov 01 04:00:00 EST 1987

OSTI ID:6832588

Rostoker, G; Eastman, T

Magnetospheric-substorm activity is presently understood as the combined effect of energy transport and dissipation directly driven through the solar-terrestrial interaction and of the unloading of energy stored in the magnetotail. Many studies of particle and field signatures of substorms in the magnetotail have led to the proposal that a neutral line forms close to the Earth at the time of expansive phase onset with the plasma-sheet population on the anti-Earthward side of the neutral line ultimately being lost to the solar wind through the ejection of the plasmoid. This reprint presents an alternative framework in which substorm effects in the magnetosphere can be understood. Observations of magnetic-field and plasma-flow variations in the magnetotail can be explained in terms of the passage of the plasma sheet boundary layer over the satellite detecting the tail signatures. Field-aligned currents and particle acceleration processes on magnetic-field lines threading the ionospheric Harang discontinuity lead to the distinctive particle and field signatures observed in the magnetotail during substorms. Edge effects of field-aligned currents associated with the westward-traveling surge can lead to the negative Bz perturbations observed in the tail that are presently attributed to observations made on the anti-Earthward side of a near-Earth neutral line.

• Research Organization: Iowa Univ., Iowa City (USA). Dept. of Physics and Astronomy
• OSTI ID: 6832588
• Report Number(s): AD-A-194400/8/XAB; N-00014-85-K-0404
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ALIGNMENT
AURORAL OVAL
BOUNDARY LAYERS
CURRENTS
DOCUMENT TYPES
EARTH ATMOSPHERE
EARTH MAGNETOSPHERE
ENERGY TRANSFER
FLOW RATE
HARANG DISCONTINUITY
INTERACTIONS
LAYERS
MAGNETIC FIELDS
MAGNETIC STORMS
MAGNETOTAIL
PLASMA SHEET
PROGRESS REPORT
SOLAR ACTIVITY
SOLAR WIND
SURGES
VARIATIONS