Tearing at the dayside magnetopause

Journal Article · Fri May 01 00:00:00 EDT 1981 · J. Geophys. Res.; (United States)

DOI:https://doi.org/10.1029/JA086iA05p03289· OSTI ID:6385280

Quest, K B; Coroniti, F V

Initial observations of the dayside magnetopause thickness using UCLA magnetometers on board Isee 1 (International Sun-Earth Explorer) and Isee 2 indicate that this boundary may only be a few ion gyroradii thick during periods of observed southward interplanetary magnetic field (IMF). Such a thin current layer can destabilize the collisionless tearing mode, a probable first step in the reconnection sequence. We have calculated the linear growth rate assuming typical magnetopause parameters and find that it is a sensitive function of IMF orientation, magnetopause thickness, and electron number density. We also show that the finite size of the dayside magnetopause necessitates the existence of a two-dimensional tearing mode wave vector spectrum, a consequence of the inability of a thermal electron to maintain Laudau resonance with the wave for a growth period. Implications regarding reconnection are discussed.

• Research Organization: Department of Earth and Space Sciences and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, California 90024
• OSTI ID: 6385280
• Journal Information: J. Geophys. Res.; (United States), Journal Name: J. Geophys. Res.; (United States) Vol. 86:A5; ISSN JGREA
• Country of Publication: United States
• Language: English

Related Subjects

640203* -- Atmospheric Physics-- Magnetospheric Phenomena-- (-1987)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
DIMENSIONS
EARTH ATMOSPHERE
ELECTRON DENSITY
INSTABILITY
INSTABILITY GROWTH RATES
INTERPLANETARY MAGNETIC FIELDS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
MAGNETOPAUSE
MAGNETOSPHERE
PLASMA INSTABILITY
PLASMA MACROINSTABILITIES
TEARING INSTABILITY
THICKNESS