@article{oai:nipr.repo.nii.ac.jp:00001994,
 author = {Fujita,Shigeru and Owada,Takeshi},
 journal = {Memoirs of National Institute of Polar Research. Special issue},
 month = {Aug},
 note = {P(論文), Employing Pc 1 pulsation data obtained at the Japanese Observatory Network in an interval of 1976 to 1984 covering almost one solar cycle, it is confirmed that the Pc 1 pulsations appear more frequently in the period of the minimum solar activity than in the period of the maximum activity, in winter than in summer and in the nighttime than in the daytime. The attenuation rate of the magnetic signal intensity at this network is also obtained in the period of the minimum solar activity. In addition, diurnal variation in the lower boundary frequencies of Pc 1 events are analysed. As for the variations in occurrence of the low-latitude Pc 1 pulsations related to seasonal and solar-activity, the observational results are essentially consistent with the duct propagation theory based on the International Reference Ionosphere. Attenuation rates obtained at the network fall in the same order of magnitude as that suggested by the theory. In the final part of this paper, we consider geometrical damping of the wave field which depends on spatial spread of an incident wave in high latitudes.},
 pages = {79--91},
 title = {Occurrence characteristics of Pc 1 pulsation observed at Japanese Observatory Network},
 volume = {42},
 year = {1986}
}