Preliminary studies on the whistler observation at Great Wall Station of China, Antarctica

摘要

During the First Chinese National Antarctic Research Expedition 1984/85,observation on whistler and VLF emission was carried out by using GM type VLF broadband direction-finding receiver. The morphology of whistlers received shows two peaks of their activity at 17-20 LT around sunset and at 03-06 LT of the early morning. Whistler dispersion is greater during sunset and less after midnight. Detailed analysis of whistler data of Januray 23 and 26 at Great Wall Station reveals that the dispersions of whistlers propagating in different shells markedly decrease on the day of geomagnetic storm commencement (January 23). It implies a rapid depletion of the electron density in the shells. There is a downward flux of electron of 1×(10)^9el/(cm)^2s. A steady refilling process occurs in shells of L-2.8-2.9 three days after the storm on January 26. Whistler direction-finding data obtained on January 20 show that the exit points of the whistlers are situated in a strip of about 80km wide in longitudes whith an azimuthal direction 20°-40°E of N between 48°-52° geomagnetic latitude, and there are no obvious cross L or longitudinal drifts. Whistler data at Great Wall Station are very useful for deducing temporal and spatial variations of electron density in L-2-3 shells and investigating particle interchange processes between the ionosphere and the plasmasphere.