超低周波のプラズマ波の伝送に対するイオン圏効果
まとめ
超低周波のプラズマ波は,現地時間に応じて異なった電離圏伝送特性を示しています. これらの磁気圏波の方向平面の傾きは,現地昼と比べて現地夜に大きい.
科学分野:
- 宇宙物理学 宇宙物理学
- 地質物理学 地質物理学とは地質物理学です.
- プラズマ物理学 プラズマ物理学
背景:
- 磁気圏の超低周波 (ULF) プラズマ波は,宇宙天候を理解する上で極めて重要です.
- イオノスフィアは,磁気圏から地上にULF波の伝播を著しく影響する.
研究 の 目的:
- ULFプラズマ波のイオノスフィアの伝送特性の局所時間依存性を調査する.
- 連続的な昼間照明の場所 (南極) と昼夜照明の結合ステーション (ケベック州) の間の波の伝播特性を比較する.
主な方法:
- ULFのプラズマ波 (期間18-150秒) の地上での測定が行われました.
- 継続的に太陽に照らされた南極のステーションからのデータは,昼夜サイクルを経験するケベック州のステーションと比較されました.
- イオノスフィアに対する波伝達の方向平面の傾きを分析した.
主要な成果:
- ULF波のイオノスフィアの伝達において,有意な局所時間依存が観察されました.
- 波の向きの平面の傾きは,現地正午に,現地夜よりも大きいことが判明しました.
- 南極とケベック州のステーションを比較すると,伝送特性の違いが明らかになりました.
結論:
- ULF波に対するイオノスフィアの伝送特性は,現地時間に大きく依存しています.
- 昼夜太陽光照明サイクルは,磁気圏のULF波が地面に到達する行動に影響します.
- これらの観測された局所時間変動の背後にあるメカニズムを完全に解明するには,さらなる研究が必要です.
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