A theoretical study of magnetohydrodynamic instabilities in non-rotating and rotating magnetospheric plasmas
Project/Area Number |
20540436
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Space and upper atmospheric physics
|
Research Institution | The University of Tokyo |
Principal Investigator |
MIURA Akira 東京大学, 大学院・理学系研究科, 助教 (20126171)
|
Project Period (FY) |
2008 – 2012
|
Project Status |
Completed (Fiscal Year 2012)
|
Budget Amount *help |
¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
Fiscal Year 2012: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2011: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2010: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2009: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
Fiscal Year 2008: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000)
|
Keywords | 磁気圏 / 電離層 / 磁気流体(MHD)不安定性 / プラズマ / 単極子磁気圏 / 双極子磁気圏 / エネルギー原理 / 磁気圏のエネルギー原理 / 交換型不安定 / 電磁流体不安定 / 磁気圏ー電離層結合 / 磁気圏・電離圏 / 宇宙空間 / 超高層物理学 / 磁気流体不安定性 / プラズマ・核融合 / バルーニング不安定 / 電離層駆動型交換型不安定 / 圧力駆動型交換型不安定 / 非回転の磁気圏モデル / 内部磁気圏 |
Research Abstract |
A new magnetospheric energy principle was constructed for spherically symmetric monopolar magnetospheres with magnetic field lines extending to infinity. By using eikonal assumption, I showed the existence of ionosphere-driven magnetohydrodynamic (MHD) instabilities for spherically symmetric monopolar magnetospheres and for magnetospheres with closed field lines. For an arbitrary closed magnetospheric configuration, which includes a dipole field, a general stability criterion was obtained for pressure-driven interchange instability. A nonideal MHD eigenmode equation was derived for a velocity shear instability, which is driven by a shear in the ion diamagnetic drift velocity in sheared magnetic fields, and a general stability criterion was obtained.
|
Report
(7 results)
Research Products
(39 results)