A broad-band vlf-burst associated with ring-current electrons

Technical Report · Mon Mar 01 04:00:00 EST 1982

OSTI ID:6511474

Maeda, K

Frequency band broadening takes place just outside of the nighttime plasmasphere, where the density of cold plasma is known to be very low during the later phase of a geomagnetic storm. Instead of the gradual broadening of several hours duration, a burst type broadening of VLF emission lasting less than ten minutes was observed by Explorer 45 in a similar location. The magnetic field component of this emission is very weak and the frequency spreads below the local half electron cyclotron frequency. Corresponding enhancement of the anisotropic ring current electrons is also very sudden and limited below the order of 10 keV without significant velocity dispersion, in contrast to the gradual broadening events. The cause of this type of emission band spreading can be attributed to the generation of the quasielectrostatic whistler mode emission of short wavelength by hot bimaxwellian electrons surging into the domain of relatively low density magnetized cold plasma. The lack of energy dispersion in the enhanced electrons indicates that the inner edge of the plasma sheet, the source of these hot electrons, is not far from the location of this event.

• Research Organization: National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center
• OSTI ID: 6511474
• Report Number(s): NASA-TM-83923
• Country of Publication: United States
• Language: English

Related Subjects

640201* -- Atmospheric Physics-- Auroral
Ionospheric
& Magetospheric Phenomena
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CURRENTS
CYCLOTRON FREQUENCY
EARTH ATMOSPHERE
ELECTRIC CURRENTS
ELECTRON EMISSION
EMISSION
EXPLORER SATELLITES
FREQUENCY RANGE
HZ RANGE
MAGNETIC STORMS
MAGNETOSPHERE
PLASMAPAUSE
RING CURRENTS
SATELLITES