1999 Fiscal Year Final Research Report Summary
A study of mid-latitude field-aligned currents
| Project/Area Number |
10640430
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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 | KYOTO UNIVERSITY |
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Principal Investigator |
IYEMORI Toshihiko Graduate School of Science, Kyoto Univ., Professor, 大学院・理学研究科, 教授 (40144315)
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| Co-Investigator(Kenkyū-buntansha) |
TAKEDA Masahiko Graduate School of Science, Kyoto Univ., Instructor, 大学院・理学研究科, 助手 (30236484)
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| Project Period (FY) |
1998 – 1999
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| Keywords | field-aligned current / mid-latitude / ionospheric current / magnetospheric current / MU radar / HF radar / neutral wind |
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| Research Abstract |
1. The magnetic effects from mid-latitude field-aligned currents have been estimated from a model calculation and compared with the ground geomagnetic observations as well as the Oersted satellite observations. It has been shown by a model calculation that the field-aligned current effects strongly depend on the dip angle of geomagnetic main field just over the ionospheric altitude. From the satellite observation, the existence of a net current system which flows into the ionosphere on the day side and flows out on the night side has been confirmed.
2. The existence of the mid-latitude field-aligned current has been confirmed by a statistical analysis of the DE-2 satellite magnetic observation.
3. A comparison of the MU radar electric field observation and ground geomagnetic field variation suggested that the most of the ground geomagnetic perturbation come from the magnetospheric current system which include the field-aligned currents.
4. From a statistical analysis of the HF radar observation, it has been found that the occurrence frequency of ionospheric irregularities has a peak distribution around the terminator on the dusk side.
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