太陽の南極上空:低エネルギー惑星間電荷粒子
L J Lanzerotti1, T P Armstrong, R E Gold
1AT&T Bell Laboratories, Murray Hill, NJ 07974, USA.
Science (New York, N.Y.)
|May 19, 1995
まとめ
ヘリオスフィアの電流シートは,極地でも,ヘリオスフィアを大きく形作る. 惑星間衝撃は,ユリセスから遠く離れた電子を加速させた.
科学分野:
- 宇宙物理学 宇宙物理学
- ヘリオフィジックス ヘリオフィジックス
- プラズマ物理学のプラズマ物理学
背景:
- ヘリオスフィアの構造は,太陽の活動と磁場の影響を受けます.
- ヘリオスフィアの粒子輸送を理解することは,宇宙天候の予測に不可欠です.
研究 の 目的:
- 南極地域における粒子流動にヘリオスフィアの電流シートの影響を調査する.
- 低エネルギーイオンと電子の加速機構を分析する.
主な方法:
- ユリセス宇宙船のスペクトル,組成,およびアニソトロピー (HISCALE) のヘリオスフィア機器からのデータを利用しました.
- 極の交差時に低エネルギーイオンと電子 (> 50 keV) の分析された流れ.
主要な成果:
- ヘリオスフィアの電流シートは,ヘリオスフィアの構造を -75°ヘリオ緯度まで大きく影響した.
- 惑星間逆衝撃は,ユリセス宇宙船から遠く離れた電子を加速させた.
- 異常な酸素流量とNe/O比率は,高ヘリオ緯度で測定されました.
結論:
- ヘリオスフィアの電流シートは,ヘリオスフィアの形成に支配的な役割を果たしています.
- 粒子加速は,現在のシートダイナミクスと惑星間ショックに関連しています.
- より高いヘリオ緯度における低エネルギー電子流量増強を明確にするために,さらなる研究が必要である.
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