| Project/Area Number |
09640535
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Space and upper atmospheric physics
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| Research Institution | The University of Tokyo (1999)
Institute of Space and Astronautical Science (1997-1998) |
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Principal Investigator |
HOSHLNO Masahiro Graduate School of Science, The University of Tokyo, Professor, 大学院・理学系研究科, 教授 (90241257)
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| Project Period (FY) |
1997 – 1999
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| Project Status |
Completed (Fiscal Year 1999)
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| Budget Amount *help |
¥3,100,000 (Direct Cost: ¥3,100,000)
Fiscal Year 1999: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 1998: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1997: ¥1,500,000 (Direct Cost: ¥1,500,000)
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| Keywords | Magnetic Reconnection / Plasma Kinetics / Magnetotail / Ballooning Instability / Numerical Simulation / GEOTAIL Satellite / MHDシミュレーション / 衝撃波 / プラズマ・シート / プラズモイド / ジオテイル衛星 / バル-ニング不安定 |
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| Research Abstract |
Our objective is to understand both the kinetic behavior of magnetic reconnection in the Earth's magnetotail and its related plasma instabilities. Firstly, on the basis of the GEOTAIL satellite observations, it is found that the thickness of the macroscopic plasma sheet becomes of the order of the ion gyro-radius in the Earth's magnetotail reconnection. This observation is suggestive the existence of a strong coupling system between the macro-scale and the micro-scale with the magnetic reconnection. We studied the small-scale plasma dynamics where the Hall electric current plays an important role on the evolution of the global plasma sheet structure. By using a large-scale particle-in-cell simulation, we found that (1) the magnitude of Hall electric current becomes of the order of the dawn-dusk reconnection electric current, (2) the strong Hall electric current can excite the large electric fields in the reconnection plane, (3) the wave-particle interaction of the excited electric field and electrons can produce a wide variety of non-Maxwell electron distribution functions, and (4) the high energy non-thermal electrons are also produced during the above process. We have also studied the coupling of the reconnection mode to the interchange mode such as the ballooning mode in the resistive MHD framework. Several preliminary important results that should be studied further were found.
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