@article{oai:nagoya.repo.nii.ac.jp:00020105, author = {Nishino, Masanori and Takeo, Koji and Katoh, Toshio and Tanaka, Yoshihito}, journal = {Proceedings of the Research Institute of Atmospherics, Nagoya University}, month = {Mar}, note = {Group travel times and arrival directions of the whistler-mode signals from VLF transmitter in Eastern USSR were measured at the geomagnetic conjugate point (geomag. lat. 40.2°S; L = 1.93) in South Australia. The dispersion values obtained by the group travel times were almost the same around sunset at the two frequencies of 14.881 kHz and 11.905 kHz. The arrival directions of the 14.881 kHz whistler-mode signals were mainly distributed around the magnetic field line intersecting the receiver. These results indicate that the mid-latitude whistler-mode waves propagate in a field-aligned duct and penetrate through the low-latitude ionosphere of the receiver. A comparison between the group travel times around sunset on two geomagnetically quiet days is discussed based on the measurements of arrival directions and intensities of the whistler-mode signals.}, pages = {3--16}, title = {DUCTED PROPAGATION OF VLF WHISTLER-MODE SIGNALS AT L=1.93 AS DEDUCED FROM MEASUREMENTS OF GROUP TRAVEL TIMES AND ARRIVAL DIRECTIONS}, volume = {37}, year = {1990} }