惑星性星雲ヘニゼ 2-428の二重変異した超チャンドラセカール核
M Santander-García1, P Rodríguez-Gil2, R L M Corradi2
11] Observatorio Astronómico Nacional, Apartado de Correos 112, E-28803, Alcalá de Henares, Spain [2] Instituto de Ciencia de Materiales de Madrid (CSIC), Sor Juana Inés de la Cruz, 3, E-28049 Madrid, Spain.
Nature
|February 18, 2015
まとめ
天文学者たちは,二重変態の恒星系であるヘニゼ2−428を発見し,その質量はチャンドラセカルの限度を超えている. この発見は,超チャンドラセカール型Ia超新星における二重変性経路を支持する.
科学分野:
- 天体物理学 天体物理学
- 恒星の進化について
- 惑星の星雲は惑星の星雲です.
背景:
- 惑星星雲は,1〜8Mの恒星から形成される.
- 複雑な惑星星雲の形状は十分に理解されていないが,提案されたメカニズムとして二次相互作用がある.
- ダブルデジェネレート系は,2つの白矮星で構成され,その2つの白矮星は封筒を外した.
研究 の 目的:
- 複雑な惑星星雲の形態の起源を調査する.
- 型Ia超新星の進化経路を決定する.
- Henize 2-428 システムを分析する.
主な方法:
- 観測天文学は,観測による天文学である.
- 恒星の進化モデリング
- バイナリーシステムのパラメータ (質量,軌道周期) の分析.
主要な成果:
- ヘニゼ2−428は,二重変性系で,総質量は約1.76Mである.
- この質量は,Chandrasekharの限界である1.4Mを上回っている.
- このシステムは,4.2時間の短い軌道周期を持ち,7億年後に合体すると予測されています.
結論:
- Henize 2-428システムは,タイプ Ia 超新星に対する二重変性,超チャンドラセカルの進化経路をサポートしています.
- この発見は,超新星形成の重要なメカニズムについての観察的証拠を提供します.
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