マシブなヘリウム星で,磁場が十分に強く,磁星を形成する
Tomer Shenar1, Gregg A Wade2, Pablo Marchant3
1Anton Pannekoek Institute for Astronomy, University of Amsterdam, 1098 XH Amsterdam, Netherlands.
まとめ
研究者らはHD 45166系に強い磁場を持つ ウォルフ・レイエの星を特定しました この恒星は超新星爆発後に 磁性強い中性子星の一種である マグネタールを形成すると予測されています
科学分野:
- * 天体物理学
- * 星の進化
- * 中性子星形成
背景:
- * マグネターは非常に強い磁場を持つ中性子星ですが,その起源は不明です.
- * ウォルフ・レイエの星は,熱い,ヘリウムに富んだ星で,そのスペクトルの放射線が特徴です.
- マグネターのような 異星的な恒星残骸の形成経路を理解することは 天体物理学にとって極めて重要です
研究 の 目的:
- * 二重星系HD45166の性質を調査する
- * システム内のウルフ・ライエット星の性質を決定する.
- * マグネタールの形成の可能性を調査する.
主な方法:
- * HD 45166システムのスペクトロポリメトリック観測.
- * バイナリーシステムのアーカイブ軌道データの再分析.
- * 恒星の進化モデルと計算
主要な成果:
- * HD 45166系には,太陽の2倍の質量を持つウルフ・レイエの星がある.
- * ウォルフ・レイエの星には43キロガウスの磁場が観測された.
- * 星の進化の予測は,マグネタール残骸につながる超新星爆発を示しています.
結論:
- * 観測されたウルフ・レイエの星は,磁星を形成するのに十分な磁場強さを持っています.
- * この磁気化されたウルフ・レイエットの星形成のシナリオは 質量が低い2つのヘリウム星の合体です
- * この研究は,巨大な恒星からの磁星形成の潜在的な経路を提供します.
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