2016 Fiscal Year Final Research Report
A role of the low latitude ionosphere as an electromagnetic energy transmission path in the magnetosphere-ionosphere coupled system
Project/Area Number |
26400481
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Space and upper atmospheric physics
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Research Institution | Kibi International University |
Principal Investigator |
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Co-Investigator(Renkei-kenkyūsha) |
TOMIZAWA Ichiro 電気通信大学, 宇宙・電磁環境研究センター, 准教授 (50111696)
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Research Collaborator |
Bhasakara Veenadhari
Dalia Buresova
Jaroslav Chum
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Project Period (FY) |
2014-04-01 – 2017-03-31
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Keywords | 低緯度電離圏電場 / HF Doppler サウンダー / 赤道ジェット電流 / 磁気圏対流電場 / 過遮蔽電場 / 地磁気脈動 / サブストーム / 磁気嵐 |
Outline of Final Research Achievements |
To verify the role of the mid and low latitude ionosphere as an electromagnetic energy transmission path to the inner magnetosphere and magnetotail, we analyzed space weather disturbances such as the geomagnetic sudden commencements and substorms with HF Doppler sounder and magnetometer observations. We found that the electric field at low latitude is highly correlated with the magnetic disturbances caused by the equatorial electrojet. We suggest that the electromagnetic energy is transmitted from high latitude to the equator on the nightside as well as on the dayside, and drives electrojets in the nighttime equatorial ionosphere. We clarified quantitative relationship between the low latitude electric field and equatorial electrojet as a function of the solar zenith angle, which would help estimate the low latitude ionospheric electric field of the past major geomagnetic storms.
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Free Research Field |
磁気圏電離圏物理学
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