Direction finding of auroral VLF hiss in auroral zone

Abstract

A newly developed direction finding ('DF') for auroral hiss based on the measurement of time differences of wave arrival among three spaced points was carried out around Syowa Station (geomag. lat. -70.4°), Antarctica in 1978-1979. It has been found that the new DF can determine localized exits of VLF auroral hiss with an accuracy of about 10°. A comparison of the DF results with the ground-based auroral data has shown that impulsive type auroral hiss with a wide-band frequency range has not emerged from the whole region of bright aurora but from some localized regions of bright electron auroras at the ionospheric level, and that the arrival directions of auroral hiss change rapidly in accordance with the auroral movements.