@article{oai:nagoya.repo.nii.ac.jp:00020070, author = {IWATA, Akira and ISHIKAWA, Haruji and TAKAGI, Masumi}, journal = {Proceedings of the Research Institute of Atmospherics, Nagoya University}, month = {Mar}, note = {Electro-static field changes and VLF pulses due to a lightning discharge were measured at the close-to-thunderstorm field site, while slow tail atmospherics and VLF pulses originating from that discharge, were simultaneously measured at the two distances, i.e., 350 km and 1000 km from the source discharge respectively. Coincident recording of, electro-static field changes and VLF pulses at the source, and slow tail atmospherics at the two distances were succeeded for return strokes, but it did not succeed for cloud discharges in 1969. The initial porality of the slow tail atmospherics coincidently obtained at the two distances are found to be positive. This indicates that the electric current flows from antenna to ground of the slow tail instrument, accordingly we get the evidence that the positive electricity, which is induced on the top of a vertical antenna at the source under the influence of negatively charged thunder-cloud base, is released to ground at the moment of cloud-to-ground discharge on-set. The result is consistent with the theoretical deduction which assumes the return stroke to be a downward vertical dipole moment on the ground.}, pages = {13--21}, title = {SLOW TAIL ATMOSPHERICS AND THEIR ORIGIN}, volume = {17}, year = {1970} }