Intense Electrostatic Waves Near the Upper Hybrid Resonance Frequency.
IOWA UNIV IOWA CITY DEPT OF PHYSICS AND ASTRONOMY
Pagination or Media Count:
Plasma wave measurements using instruments on the IMP 6 and Hawkeye 1 satellites are utilized in a study of very intense electrostatic waves near the upper hybrid resonance frequency in the region just outside the plasmapause. These intense plasma wave events have electric field strengths of about 1 to 20 mVm and are among the most intense waves seen in the earths magnetosphere. Detailed studies of more than 140 of these intense electrostatic disturbances reveal that the events occur at all local times and at magnetic latitudes varying from the equator to as high as 50 deg. The polarization of these waves is such that the wave electric field vector is oriented perpendicular to the geomagnetic field. In most cases the center frequency of the intense waves appears to correspond to an n 12f- sub g harmonic near the upper hybrid resonance frequency. A possible mechanism for producing intense waves near the upper hybrid resonance frequency is suggested which draws upon current theories applied to the generation of n 12f- sub g bands. Evidence is given which suggests the intense electrostatic waves may be a source of nonthermal continuum radiation.
- Atmospheric Physics