Cusp width and B: Observations and a conceptual model

Journal Article · Tue Dec 01 04:00:00 EST 1987 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA092iA12p13673· OSTI ID:5597424

Newell, P T; Meng, C

Because a southward turning of the interplanetary magnetic field B/sub z/ enhances dayside merging, leading to an equatorward motion of the equatorward edge of the cusp, one might suppose that the cusp latitudinal width whould be larger for a southward B/sub z/ condition. The Defense Meteorological Satellite Program F7 observations confirm two previous case studies showing that the cusp low-altitude latitudinal extent is actually narrower when B/sub z/ is southward than when B/sub z/ is northward. The earlier studies dealt with intense geomagnetic storms; examples presented here show that it is routine to observe a narrowing of the cusp width following a southward turning of B/sub z/. In addition, we present a simple conceptual model that shows how enhanced tailward convection of the newly opened field lines during periods of southward B/sub z/ can account for the observed narrowness. copyright American Geophysical Union 1987

• Research Organization: The Johns Hopkins University, Applied Physics Laboratory, Laurel, Maryland
• OSTI ID: 5597424
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 92:A12; 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
AURORAE
CHARGED-PARTICLE PRECIPITATION
DAILY VARIATIONS
DATA
ELECTRON PRECIPITATION
EXPERIMENTAL DATA
GEOGRAPHICAL VARIATIONS
INFORMATION
INTERPLANETARY MAGNETIC FIELDS
LATITUDE EFFECT
MAGNETIC FIELDS
MAGNETIC STORMS
MAGNETOSHEATH
NUMERICAL DATA
POLAR CUSP
POLAR-CAP AURORAE
VARIATIONS