HR: 1340h
AN: SM13B-1311    [Abstracts]
TI: Ionospheric signature of flow bursts in the magnetotail: Geotail-SuperDARN conjunction study
AU: * Hori, T
EM: horit@stelab.nagoya-u.ac.jp
AF: Solar Terrestrial Environment Laboratory, Nagoya University, Furou-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
AU: Hosokawa, K
EM: hosokawa@ice.uec.ac.jp
AF: Univ. of Electro-Communications, Chofu, Tokyo, 182-8585, Japan
AU: Miyashita, Y
EM: miyasita@stp.isas.jaxa.jp
AF: Institute of Space and Astronautical Sciences, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, 229-8510, Japan
AU: Ohtaka, K
EM: ohtaka@nict.go.jp
AF: National Institute of Information and Communications Technology, Koganei, Tokyo, 184- 8795, Japan
AU: Kunitake, M
EM: kunitake@nict.go.jp
AF: National Institute of Information and Communications Technology, Koganei, Tokyo, 184- 8795, Japan
AU: Watari, S
EM: watari@nict.go.jp
AF: National Institute of Information and Communications Technology, Koganei, Tokyo, 184- 8795, Japan
AU: Kikuchi, T
EM: kikuchi@stelab.nagoya-u.ac.jp
AF: Solar Terrestrial Environment Laboratory, Nagoya University, Furou-cho, Chikusa, Nagoya, Aichi, 464-8601, Japan
AU: Saito, Y
EM: saito@stp.isas.jaxa.jp
AF: Institute of Space and Astronautical Sciences, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, 229-8510, Japan
AU: Mukai, T
EM: mukai@stp.isas.jaxa.jp
AF: Institute of Space and Astronautical Sciences, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, 229-8510, Japan
AB: Ionospheric convection signatures associated with flow bursts in the magnetotail are examined statistically on the basis of the simultaneous observations made by the Geotail spacecraft and the SuperDARN radars covering the footprint of Geotail. Our statistical study shows that most (~ 82 %) of the flow bursts in the magnetotail are accompanied by a significant enhancement of the ionospheric convection flow at the footprint of Geotail mapped along the field line. Generally the magnetotail flows enhance and decay rapidly, while the corresponding ionospheric flows develop as quickly but tend to fade away gradually. However, the start time of most of the magnetotail tail flows coincides with that of the ionospheric flow enhancements within a few minutes. Both the spatial and temporal correspondence suggests that those flow bursts take place as a M-I-coupled process. While the ionospheric convection often shows an overall enhancement of the nightside part of the dawn or dusk convection cell, the most significant enhancement tends to take place at or near the foot point of the corresponding magnetotail flow bursts. There the ionospheric flow enhancement appears as an uniform convection channel or a local shear/vortex-like convection cell. Both types of convection enhancement are found with roughly the same probability, regardless of the magnetotail flow characteristics. How a flow burst in the magnetotail can have those different counterparts on the ionospheric side will be discussed by considering substorm effects as well as the spatial characteristics of the flow bursts and the ionosphere.
DE: 2700 MAGNETOSPHERIC PHYSICS (6939)
DE: 2736 Magnetosphere/ionosphere interactions (2431)
DE: 2760 Plasma convection (2463)
SC: SPA-Magnetospheric Physics [SM]
MN: 2007 Fall Meeting