バイナリミリ秒パルサーの回転と増積力の間の振動
A Papitto1, C Ferrigno, E Bozzo
1Institute of Space Sciences (ICE; IEEC-CSIC), Campus UAB, Faculty of Science, Torre C5, Parell, 2a Planta, E-08193 Barcelona, Spain. papitto@ice.csic.es
Nature
|September 27, 2013
まとめ
バイナリ系の中性子星は,物質の蓄積とX線の放出と,磁場を通して回転してラジオパルスを生成する間で切り替えることができます. この研究では,中性子星がこの2つの状態の間の移行を観察し,その進化的つながりを確認しました.
科学分野:
- 天体物理学 天体物理学
- 高エネルギー天体物理学
- 中性子星物理学 中性子星物理学
背景:
- 低質量バイナリ系にある中性子星は,物質と角運動量を蓄積することで,ミリ秒周期まで回転すると考えられている.
- 収縮段階は,明るいX線放射 (低質量X線バイナリ) が特徴であり,後期の段階は,回転によって駆動される無線ミリ秒パルサーが特徴です.
研究 の 目的:
- 集積動力パルサーと回転動力パルサーの間の移行に関する直接的な観測証拠を提供する.
- 中性子星の二重星系の急速な状態転換能力を調査するために.
主な方法:
- 以前は回転動力を持つ電波パルサーと特定された中性子星のミリ秒間X線パルサーションの観測.
- ラジオパルス検出のモニタリング,X線爆発後のX線パルス検出.
主要な成果:
- 以前は回転動力による電波パルサーとして観測されていた中性子星からの,増殖動力による,ミリ秒間のX線パルサーの直接検出.
- 1ヶ月間のX線爆発の数日後,ラジオパルスの再検出が,急速な状態変化を示しています.
結論:
- 観測された移行は,低質量X線バイナリと回転動力ミリ秒パルサーとの間の進化的つながりの強力な証拠を提供します.
- いくつかの中性子星系が,短時間スケールで,蓄積動力と回転動力による状態をすばやく切り替えることができることを示しています.
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