地球の磁気断層における継続的な磁気再接続
H U Frey1, T D Phan, S A Fuselier
1Space Sciences Laboratory, University of California, Berkeley, California 94720-7450, USA. hfrey@ssl.berkeley.edu
Nature
|December 5, 2003
まとめ
地球の磁気圏への太陽風の侵入に不可欠な磁気再接続は,常に断続的ではなく,継続的であり得る. その安定性は,磁気停滞期における太陽風の駆動条件に依存する.
科学分野:
- 宇宙物理学 宇宙物理学
- プラズマ物理学 プラズマ物理学
- 地質物理学 地質物理学とは地質物理学です.
背景:
- 磁気再接続により,太陽風のプラズマが地球の磁気圏に侵入することが容易になる.
- 磁気再接続の断続的または継続的な性質は,長年の疑問です.
- 再接続に関連した太陽フレアとサブストームは,バーストのような行動を示します.
研究 の 目的:
- マグネトパウズにおける磁気再接続が本質的に断続的であるか,または継続的であるかどうかを調査する.
- マグネトパウズ再接続の時間的行動に影響を与える要因を決定する.
主な方法:
- マグネトパウスの再接続のリモートシグネチャーとして,イオノスフィアの昼間のプロトンオーロラスポットの観測分析.
- オーロラ斑の存在と太陽風の条件の相関.
主要な成果:
- 継続的で準安定した磁気再接続は,地球の高緯度磁気断層で長期間観察されました.
- 再接続のインジケーターである昼側プロトンオーロラスポットは,何時間も継続的に存在していました.
- 再接続は,太陽風によって直接駆動されていることが判明しました.
結論:
- 磁気再接続は本質的に断続的ではない.
- 磁気再接続の安定性は,運転条件,特に太陽風に依存しています.
- 継続的な再接続は,太陽風によって適切に駆動された場合,磁気停止時に発生することができます.
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