NGC 5907の超光るX線源を駆動する極限特性のパルサー
Gian Luca Israel1, Andrea Belfiore2, Luigi Stella3
1Osservatorio Astronomico di Roma, Istituto Nazionale di Astrofisica (INAF), via Frascati 33, I-00078 Monteporzio Catone, Italy. gianluca@oa-roma.inaf.it.
Science (New York, N.Y.)
|February 22, 2017
まとめ
超光るX線源 (ULXs) は,ブラックホール (BHs) だけでなく,中性子星 (NSs) の増加である可能性があります. 観測により,NGC 5907 ULXは異常な明るさを持つNSであり,他のULXもNSを宿している可能性があることを示唆している.
科学分野:
- 天体物理学
- 高エネルギー天体物理学
- X線天文学
背景:
- 超光るX線源 (ULXs) は,近くの銀河の例外的に明るいX線放射源である.
- 通常は,恒星質量ブラックホール (BHs) または中間質量ブラックホール (BHs) としてモデル化されます.
研究 の 目的:
- NGC 5907の超光X線源 (ULX) の性質を調査する.
- ULXのブラックホールモデルに 異議を唱え 代替説明を探る
主な方法:
- NGC 5907 ULXの観測データを提示しました.
- 2003年から2014年のスピン周期の進化を分析した.
- 観測された光度と標準増量モデルを比較し,磁場効果を調査した.
主要な成果:
- NGC 5907 ULXをブラックホールではなく,増量中性子星 (NS) として特定した.
- 2003年から2014年の間,スピン周期が1.43秒から1.13秒に変化した.
- NSのエディントン限界の1000倍を超える明るさを示し,標準の蓄積モデルに逆らっています.
結論:
- NGC 5907 ULXの観測された性質を説明するために,強力な多極磁場が提案されている.
- 10^41 erg/sを超える他の極端なULXも,中性子星が蓄積している可能性があることを示唆している.
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