コーラス波による分散は,拡散したオーロラの降水の主な原因である
Richard M Thorne1, Binbin Ni, Xin Tao
1Department of Atmospheric and Oceanic Sciences, University of California, Los Angeles, 405 Hilgard Avenue, Los Angeles, California 90095-1565, USA. rmt@atmos.ucla.edu
Nature
|October 22, 2010
まとめ
静電波ではなく,コーラス波が,激しい拡散オーロラの降雨の主な原因です. この発見は,長年にわたる科学的議論を解決し,地球の磁気圏における電子の振る舞いを説明します.
科学分野:
- 宇宙物理学 宇宙物理学
- 磁気圏物理学 磁気圏物理学
- 大気科学 大気科学
背景:
- 拡散オーロラは,磁気圏からの低エネルギー電子の降水によって引き起こされます.
- この降水は,高緯度の夜間上層大気圏に大きな影響を及ぼします.
- 拡散オーロラにつながる電子散乱の正確な原因は議論されている.
研究 の 目的:
- 拡散オーロラ電子の降水の原因となる支配的な磁気圏のプラズマ波を決定する.
- 静電電子サイクロトロンハーモニク波とウィスラーモードコーラス波の間の論争を解決するために.
主な方法:
- 衛星観測による磁気圏プラズマ波データの分析.
- 電子散乱をモデル化するためのフォッカー・プランクの拡散計算.
- 波の活動と拡散した北極の降雨の強さの相関.
主要な成果:
- ホイッスルモードの合唱波による分散は,激しい拡散オーロラ降雨の支配的な原因として特定されています.
- コーラス波の散乱は,磁気圏の漂流中に電子の除去を説明する.
- コーラス波の散乱は,観測されたパンケーキの電子分布と拡散オーロラ形態の説明である.
結論:
- ホイッスラーモードの合唱波は,拡散したオーロラ降雨の主要な原動力である.
- これは,磁気圏物理学の主要な論争を解決します.
- コーラス波の相互作用は,電子ダイナミクスとオーロラの世界的な主要な特徴を説明します.
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