パルサーの回転は,超新星による増積ショックにおける不安定から生じる
John M Blondin1, Anthony Mezzacappa
1Department of Physics, North Carolina State University, Raleigh, North Carolina 27695-8202, USA. john_blondin@ncsu.edu
Nature
|January 5, 2007
まとめ
新しい研究では,パルサーの回転を生成する超新星ショックの不安定性が明らかになりました. この発見は,観測されたパルサー周期を説明し,それらを祖先星の回転から切り離します.
科学分野:
- 天体物理学 天体物理学
- 恒星の進化について
- 中性子星物理学 中性子星物理学
背景:
- 回転力パルサーは,様々な回転周期で観測されています.
- 伝統的なモデルは,核の崩壊中の角運動量保存を通じて,パルサー・スピンを原始星の回転と結びつける.
- 恒星理論は,パルサーのスピン周期の観測された分布を説明するために苦労しています.
研究 の 目的:
- 核崩壊超新星の間に中性子星のスピンを生成するための新しいメカニズムを調査する.
- パルサーのスピン周期の観測された分布を説明するために.
- 祖星回転とパルサー回転の相関関係を再評価する.
主な方法:
- コア崩壊の超新星シミュレーションにおける停滞した蓄積の衝撃の不安定性の分析.
- プロトニュートロン星近くの回転フローの生成をモデル化した.
- プロト・ニュートロン星への角運動量積分の調査.
主要な成果:
- 停滞した蓄積ショックの強固な不安定性は,強力な回転フローを生成します.
- 観測された回転周期を達成するために,プロトニュートロン星に十分な角度運動量が積まれている.
- このメカニズムは,球形対称な初期条件でも動作します.
結論:
- 中性子星のスピン生成のための新しいメカニズムが特定されました.
- 先祖核の回転とパルサーの回転の間の直接的な相関関係が弱体化している.
- 観測されたパルサー・スピン分布は,祖先の回転だけではなく,超新星ダイナミクスによって説明できる.
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