| Summary: | 1969-03-30 Polarization and direction of arrival of VLF emissions have been observed at Showa Base in the Antarctic by using a combination of a vertical antenna and corossed loop antenna with their planes lying in geomagnetic E-W and N-S directions. The results obtained with a polarimeter show that the emissions at 750Hz, 12KHz and 25KHz were left-handed polarization wave in all seasons, if one looks towards the observation site on earth's magnetic field. But there seemed to be seasonal variation in the ratio of righthanded polarization wave to left-handed polarization wave. A pronounced evidence is that the emission at 25KHz was linearly polarized in winter (July and August). The oscillographic patterns obtained here with a direction finder seem to indicate that the emission at 12KHz simultaneously arrived from various directions, and that the emission was elliptically polarized. But some few cases, the emission seemed to come down roughly from vertical direction along a geomagnetic field line, and to be circularly polarized. departmental bulletin paper
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