The longitudinal and radial distribution of magnetic reconfigurations in the near-earth magnetotail as observed by AMPTE/CCE

Journal Article · Mon Feb 01 00:00:00 EST 1988 · Journal of Geophysical Research; (United States)

DOI:https://doi.org/10.1029/JA093iA02p00997· OSTI ID:6050473

Lopez, R E ^[1]; Lui, A T.Y.; Sibeck, D G; McEntire, R W; Zanetti, L J; Potemra, T A; Krimigis, S M ^[2]

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1. Applied Research Corp., Landover, MD (United States)
2. Johns Hopkins Univ., Laurel, MD (United States)

Magnetic field and energetic particle data from the AMPTE/CCE have been used to identify 103 magnetic reconfiguration events in the near-Earth (R{le}8.8R{sub E}) nightside equatorial plane. The events involve a dipolarization of the magnetic field and increases in energetic particle fluxes typical of substorms. This study is the first survey of such signatures extended over both local time and radial distance. The events are distributed in magnetic local time (MLT) from 19.9 MLT to 4.7 MLT with the peak of the distribution near midnight. No events were observed inside of 6.4 R{sub E}, and the occurrence frequency increased with radial distance. For Kp{le}3-, the local time peak of the distribution in near 23 MLT, whereas for Kp{ge}4+, the distribution center is near 2 MLT. Furthermore, the occurrence frequency of the events when Kp{ge}4+ is 4 times greater than the occurrency frequency for events when Kp{le}3-. The results of this study suggest that (1) substorm reconfiguration of the magnetic field, presumably arising from disruption/diversion of the cross-tail current, seldom reaches inside a radial distance of about 6.4 R{sub E}, and (2) the central meridian of the substorm current wedge tends to shift from the premidnight to the postmidnight sectors as the global geomagnetic activity increases.

• OSTI ID: 6050473
• Journal Information: Journal of Geophysical Research; (United States), Vol. 93:A2; ISSN 0148-0227
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
MAGNETOTAIL
MAGNETIC FIELD CONFIGURATIONS
DISTANCE
EARTH MAGNETOSPHERE
ELECTRIC CURRENTS
ELECTROJETS
EQUATOR
EXPANSION
MAGNETIC STORMS
SATELLITES
SPATIAL DISTRIBUTION
STATISTICS
SURVEYS
TIME DEPENDENCE
CURRENTS
DISTRIBUTION
EARTH ATMOSPHERE
MATHEMATICS
661320* - Auroral
Ionospheric
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