Oral Presentation

Pi2 pulsations observed by the Arase satellite inside and outside the plasmasphere

Author(s): M. Teramoto, A. Matsuoka, Y. Kasahara, Y. Kasaba, A. Kumamoto, F. Tsuchiya, S. Matsuda, M. Nosé, R. Nomura, S. Kurita, M. Shoji, S. Imajo, Y. Miyoshi, and I. Shinohara

Presenter: Mariko Teramoto (Kyushu Institute of Technology)

In this study, we investigate the characteristics of off-equatorial Pi2 pulsations on the nightside and their relation to the plasmapause, using the magnetic field, the electric field, and the electron density data from the Arase satellite. We find that the nightside Pi2 pulsations in the inner magnetosphere, which are highly coherent with those at low-latitude ground stations, are dominated by the poloidal component (the radial and compressional components for the magnetic field). The amplitudes of the compressional magnetic field have a maximum value in the vicinity of the plasmapause. The phases of Pi2 pulsations in the compressional component, relative to low-latitude Pi2 pulsations on the ground, are 0° and 180° inside and outside the plasmasphere, respectively. The profile of the amplitude and the phase of the Pi2 pulsations can be explained by a plasmaspheric virtual resonance mode [1]. In this presentation, we also show the latitudinal structure of Pi2 pulsations in the electric field.