Project/Area Number |
12680485
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
プラズマ理工学
|
Research Institution | National Institute for Fusion Science |
Principal Investigator |
ISHIGURO Seiji National Institute for Fusion Science, Theory and Computer Simulation Center, Associate Professor., 理論・シミュレーション研究センター, 助教授 (10193301)
|
Co-Investigator(Kenkyū-buntansha) |
TAKAMARU Hisanori National Institute for Fusion Science, Theory and Computer Simulation Center, Research Associate., 理論・シミュレーション研究センター, 助手 (20241234)
TODO Yasushi National Institute for Fusion Science, Theory and Computer Simulation Center, Associate Professor., 理論・シミュレーション研究センター, 助教授 (00249971)
堀内 利得 核融合科学研究所, 理論・シミュレーション研究センター, 教授 (00229220)
|
Project Period (FY) |
2000 – 2002
|
Project Status |
Completed (Fiscal Year 2002)
|
Budget Amount *help |
¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2002: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 2001: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 2000: ¥1,200,000 (Direct Cost: ¥1,200,000)
|
Keywords | aurora / particle acceleration / potential structure / double layer / anomalous resistivity / V-shaped potential structure / ionsphere / electrostatic ion-cyclotron instability / 異常低抗 / イオンサイクロトロン / 沿磁力線電位差 |
Research Abstract |
Aurora is generated by ionization of oxygen and nitrogen molecules due to collision of high speed electrons which are accelerated along magnetic field lines in the ionosphere. In order to investigate the generation mechanism of these high speed electrons, we had developed self-consisted open-boundary two and a half dimensional electrostatic particle simulation code and had succeeded in demonstrating that the V-shaped dc potential structure is created by current-driven electrostatic ion-cyclotron instability. We have performed several simulation runs to investigate attained potential difference and potential structure dependencies on the system length and the width of the current layer. It is found that the attained potential difference increases with an increase in the simulation system. This result suggests that one can get several kV potential differences for several thousand-kilometer anomalous resistivity length. This is consistent with the auroral acceleration. The width of potential structure is almost equal to the width of the current layer. Furthermore, simulation runs have been performed by choosing simulation parameters such that both of electrostatic ion-cyclotron wave and ion acoustic wave are unstable. It has been shown that the ion cyclotron wave is dominant in this situation.
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