アルゴール系にある大きな冠状回路
W M Peterson1, R L Mutel, M Güdel
1Department of Physics and Astronomy, University of Iowa, Van Allen Hall, Iowa City, Iowa 52240, USA.
Nature
|January 16, 2010
まとめ
ラジオ画像は,KIV亜巨星から発生した,アルゴルの二重星系で,大きく,持続的な冠状のループを明らかにしています. この構造は予想以上に大きく,2つの星間の強い磁気相互作用を示唆しています.
科学分野:
- * 天体物理学
- * 星の天文学 星の天文学
- * マグネトヒドロダイナミクス
背景:
- * アルゴル系は,KIV亜巨星とB8メインシーケンス恒星からなる密接なバイナリ系です.
- * 軌道周期に恒星回転の潮鎖が磁力ダイナモを駆動する.
- *証拠は,KIV亜巨星の周りに複雑な磁気圏があることを示唆しているが,その形態学と相互作用は十分に理解されていない.
研究 の 目的:
- * アルゴール系におけるKIV亜巨星のコロナの形態を調査する.
- * 冠状プラズマと同伴星B8の相互作用を理解するために.
- * 磁気圏の構造と持続性を決定する.
主な方法:
- * アルゴル系のマルチエポック無線画像.
- * 恒星の磁場構造と冠状のプラズマ収束の分析.
主要な成果:
- * 大規模で持続的な冠状回路の観測,直径約1つの亜巨大高さ.
- *ループの底は亜巨星上にあり,その頂点はB8星に向けられている.
- *観測されたループは理論的に予測されたより大きく,潜在的な磁気相互作用を示しています.
結論:
- * 恒常的で非対称な磁場構造が,アルゴル星系内の2つの星の間に並べられている.
- *観測された冠状回路の大きさは,亜巨星と同伴星との間に有意な磁気相互作用があることを示唆しています.
- *この発見は,近い二重星系における恒星の磁気圏に関する既存の理論モデルに異議を唱えている.
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