An Analysis of Pc 1 Magnetic Pulsations Observed by the 17th Japanese Antarctic Research Expedition Wintering Party (d. ULF Waves in the Magnetosphere) (Proceedings of the Second Symposium on Coordinated Observations of the Ionosphere and Magnetosphere in the Polar Regions : Part I)

Abstract

Diurnal variations of occurrence frequency of Pc 1 pulsations and relationships between Pc 1 events and Kp, Dst and K (at Syowa Station) indices have been studied by using f-t spectra of magnetic pulsations observed at Syowa and Mizuho Stations during one year from January 1976 to January 1977. It is found that the occurrence probability of Pc 1 events does not depend on the magnitude of Kp index, while there is a tendency that the occurrence probability of Pc 1 events increases greatly when the magnitude of Dst index is larger than -80 nT. It is also found that the f-t spectral patterns of Pc 1 events observed at Syowa and Mizuho Stations were generally quite similar to each other. However, several Pc 1 events were observed only at Syowa Station. Furthermore, dynamic polarization patterns of three typical Pc 1 events observed at Syowa Station are given in this paper.