回転と軌道軸の不整合は,DI Herculisの異常な前行を引き起こします
Simon Albrecht1, Sabine Reffert, Ignas A G Snellen
1Leiden Observatory, Leiden University, Postbus 9513, 2300 RA Leiden, The Netherlands. albrecht@space.mit.edu
Nature
|September 18, 2009
まとめ
DI Herculisのバイナリ・スター・システムです.
科学分野:
- 天体物理学 天体物理学
- 軌道ダイナミクス 軌道ダイナミクス
- 恒星の進化について
背景:
- バイナリー星の軌道は,一般相対性理論と恒星の特性により,プレセーションを示します.
- DI Herculis システムは,観測されたと理論的なプレセーション率の間の大きな不一致を示しています.
- この不一致は,歴史的に重力物理学の理解に挑戦してきた.
研究 の 目的:
- DI Herculis二進星系における異常な precession 速度の30年前の謎を解明するためです.
- 双星の軌道ダイナミクスにおける恒星のスピン軸の向きの役割を調査する.
- 理論的な予測と DI Herculis.の観測データを調和させるため.
主な方法:
- DI Herculisシステムの観測データの分析.
- 恒星の回転と傾斜を組み込む軌道前進の理論的モデリング.
- 予測されたプレセッション率と観測値の比較.
主要な成果:
- DI Herculisの両方の星は,自転軸が軌道軸にほぼ垂直である.
- この高い傾きは,回転によって誘発された恒星的平らな状態につながります.
- この平らさは,相対論的効果を相殺するプレセッションを発生させ,観測された速度が遅いことを説明する.
結論:
- DI Herculisの異常な先行は,恒星のスピン軸の垂直方向によって説明されます.
- この発見は,一般相対性理論とこの二進星系における観測を調和させるものである.
- この研究は,二重軌道ダイナミクスにおける恒星回転の重要性を強調している.
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