超光X線源からの無線放射
Philip Kaaret1, Stephane Corbel, Andrea H Prestwich
1Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138, USA. pkaaret@cfa.harvard.edu
まとめ
超明るさのX線源から検出されたラジオ放射は,相対論ジェットを持つ恒星質量ブラックホールである可能性を示唆しています. この発見は,そのような多くの源が,中間質量ブラックホールではなく,恒星質量ブラックホールであることを示す可能性があります.
科学分野:
- 天文学と天体物理学について
- 高エネルギー天体物理学 高エネルギー天体物理学
- ブラックホール物理学 ブラックホール物理学
背景:
- 超光るX線源 (ULXs) の性質は不明であり,2つの主要な仮説がある:星質のブラックホールがビーム放射を放つか,または中等質量のブラックホールがイソトロピック放射を放つ.
- これらの可能性を区別することは,ブラックホールの集団と蓄積物理学の理解に不可欠です.
研究 の 目的:
- ラジオ発射を探すことによって,超光X線源の物理的性質を調査する.
- 観測されたULXが,恒星質量または中等質量ブラックホールによって動いているかどうかを判断する.
主な方法:
- ラジオ望遠鏡を用いてNGC5408の超光るX線源からのラジオ放射の観測.
- X線,ラジオ,光学流の分析.
- X線スペクトル形状の特徴化. X線スペクトル形状の特徴化.
主要な成果:
- NGC5408のULXから放射能が検出されました.
- 観測されたX線,無線,光学流は,ビームされた相対論ジェット放射と一致しています.
- X線スペクトルの形状は,このジェット放射モデルと一致しています.
結論:
- この発見は,このULXが相対論ジェットに電力を供給する恒星質量ブラックホールであるという仮説を裏付けている.
- 確認された場合,これはULXが主に恒星質量ブラックホールによって動いている可能性があることを示唆しています.
- ジェットを生成する中等質量ブラックホールの解釈は可能性であり,排除することはできません.
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