静止しているX線バイナリの密度頂点,銀河の中央パーセック
Charles J Hailey1, Kaya Mori1, Franz E Bauer2,3,4
1Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, Room 1027, New York, New York 10027, USA.
Nature
|April 6, 2018
まとめ
天文学者は静止しているX線バイナリを用いて Sagittarius A*の近くで 恒星質量ブラックホールの密度頂点を検出しました この発見は銀河の動力の予測を裏付け 銀河の中心にある多くのブラックホールを示唆しています
科学分野:
- 天体物理学
- 銀河の力学
- X線天文学
背景:
- 銀河の恒星力学では,超大質量ブラックホールの近くにある恒星質量ブラックホールの"密度頂点"を予測しています.
- 銀河の中心にある Sagittarius A*は ブラックホールの密度の頂点を 探すのに最適な場所です
- これまでの探査では 20,000個のブラックホールの 理論的な予測にもかかわらず そのような密度の頂点を 検出できませんでした
研究 の 目的:
- 銀河の中心にある 恒星質量のブラックホールの密度の頂点を 調べるためだ
- 静止しているX線バイナリーを 銀河の中央パーセック内の 孤立したブラックホールの トレーサーとして利用する
主な方法:
- 射手座A*の1パーセック以内の静止状態のX線バイナリ系を観測した.
- 低エネルギー放射スペクトルを分析した
- 白い矮星などの既知の集団と比較したスペクトル特性.
主要な成果:
- Sagittarius A*の近くにある 静止しているX線バイナリを 検出した.
- 異なる低エネルギー放射スペクトルを観測し,白矮星と区別した.
- 空間分布と光度関数は 何百ものバイナリ系と 孤立したブラックホールがあることを示唆しています
結論:
- この発見は,恒星質量ブラックホールの密度の頂点に対する観測的証拠を提供します.
- これらのX線バイナリの分布は,その形成の歴史 (例えば,恒星盤または球状群) に関する洞察を提供します.
- 中性子星やブラックホールを含む重力波源のモデルを制限します.
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