1. Department of Earth and Planetary Sciences, Kyushu University, Japan
  2. Space Environment Research Center, Kyushu University, Japan
  3. Kagoshima National College of Technology, Japan
  4. National Institute of Information and Communications Technology, Japan
  5. Institute of Cosmophysical Research and Radiowaves Propagation of the Far Eastern Branch of Russian Academy of Sciences, Russia
  6. Manila Observatory, Philippines

In order to understand the electro-magnetic phenomenona in space, the Space Environment Research Center (SERC) of Kyushu University is deploying the MAGnetic Data Acquisition System of the Circum-pan Pacific Magnetometer Network (MAGDAS/CPMN). In this network, we also installed FM-CW (Frequency Modulated Continuous Wave) radars at Paratunka, Russia (PTK: Magnetic Latitude = 45.8° , Magnetic Longitude = 221.6° ), Sasaguri, Japan (SAS: M. Lat. = 23.2° , M. Lon. = 199.6° ), and Manila, Philippines (MNL: M. Lat. = 4.19° , M. Lon. = 192.4° ) to detect the ionospheric electric field variations. The FM-CW radar is a kind of HF (High Frequency) radar that can measure the ionospheric Doppler velocity, from which we can calculate the ionospheric electric fields. In the present paper we will introduce our FM-CW radar array observations and its preliminary scientific results. The results are as follows: (1) At the time of SC, dusk-to-dawn and subsequent dawn-to-dusk electric field penetrate into the low-latitude ionosphere. (2) Pi 2-associated ionospheric electric field at L = 2.05 is a manifestation of the plasmaspheric cavity mode. (3) Ground Pc 5 pulsation seems to be driven by ionospheric electric field at low and equatorial region.

A. Ikeda, A. Yoshikawa, M.G. Cardinal, K. Yumoto, M. Shinohara, K. Nozaki, B.M. Shevtsov, V.V. Bychkov, Q.M. Sugon Jr, D. McNamara Ionospheric observation using FM-CW radar array // Advances in Geosciences. Vol. 21: Solar & Terrestrial Science. 2008. P. 379-391.