ブラックホールのX線バイナリにおける爆発を通して追跡された強い円盤風
B E Tetarenko1, J-P Lasota2,3, C O Heinke1
1Department of Physics, University of Alberta, CCIS 4-181, Edmonton, Alberta T6G 2E1, Canada.
Nature
|January 25, 2018
まとめ
ブラックホールのバイナリにおける収縮円盤粘度 (α) は,アウトバースト光曲線を用いて推定される. 高いα値は,効率的な角度モメント輸送または,潜在的に磁気的に駆動されたアウトフローによる重要な質量損失を示唆する.
科学分野:
- 天体物理学と天文学
- 恒星の進化とコンパクトな物体
- プラズマ物理学と磁気水力学
背景:
- コンパクトな恒星残骸 (ブラックホール,中性子星,白矮星) への蓄積は爆発を促し,蓄積物理学への洞察を提供します.
- 粘度パラメータ α によって定量化される蓄積円盤の角運動量輸送は,爆発光曲線を形成する.
- ブラックホールや中性子星のシステムでは,前回の研究では,白矮星ではαが推定されました.
研究 の 目的:
- 観測データを用いてブラックホールの周りの蓄積円盤の粘度パラメータ (α) を推定する.
- ブラックホールの蓄積円盤における 角運動量輸送と質量損失を 駆動する物理的メカニズムを調査する.
- ブラックホールのX線バイナリで 磁気による流出と熱による風の違いを
主な方法:
- ブラックホールのX線バイナリーの21の爆発からのアーカイブX線光曲線の分析.
- 粘度パラメータ (α) を決定するためにバイエスのアプローチを蓄積モデルに適用する.
- 推定α値とバイナリの増積状態の相関分析
主要な成果:
- ブラックホールの蓄積円盤の推定粘度パラメータ (α) は0.2から1.0の範囲で,以前白矮星で発見されたものより大幅に高い.
- 高いα値は,非常に効率的な角度運動量輸送または大量流出による質量損失と一致します.
- 推定αと蓄積状態の間の相関は見つかりませんでしたので,すべての状態でアウトフローが存在することを示唆しています.
結論:
- ブラックホールの蓄積円盤の高粘度は,大規模な磁場による磁気回転の不安定性によって維持される可能性があります.
- 大量の円盤の流出が爆発の形成に起因し,円盤の質量の大きな部分を除去します.
- 観測された行動は,特定の放射線条件から独立して,熱的に駆動されたものではなく,磁気的に駆動された円盤風を示唆しています.
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