银河系中部的静止X射线二进制星体的密度顶点
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
概括
天文学家使用静止的X射线二进制系统在射箭星A*附近发现了恒星质量黑洞的密度顶点. 这一发现支持银河系动态的预测,
科学领域:
- 天体物理学
- 银河系动力学
- 射线天文学
背景情况:
- 星系恒星动力学预测超大质量黑洞附近的恒星质量黑洞的"密度顶点".
- 射手座A*的银河系中心是寻找这个预测的黑洞密度顶点的首选地点.
- 之前的搜索还没有发现这样的密度顶点, 尽管理论上预测有多达2万个黑洞.
研究的目的:
- 在银河系中心探测恒星质量黑洞的存在.
- 利用静止的X射线二进制星系作为银河系中部的黑洞的追踪器.
主要方法:
- 观测到静止的X射线二进制星系,距离射手座A*只有1个帕塞克.
- 分析了这些二进制星体的低能量辐射光谱.
- 与已知的群体进行比较,例如白矮星.
主要成果:
- 探测到十几个静止的X射线二进制星系, 位于射手座A*附近的密度顶点.
- 观测到不同的低能量的辐射光谱,使其与白矮星相差异化.
- 空间分布和亮度函数表明有数百个二进制星系和更多孤立的黑洞.
结论:
- 这些发现提供了恒星质量黑洞密度顶点的观测证据.
- 这些X射线二进制星体的分布为它们的形成历史提供了洞察力 (例如,恒星盘或球状星团).
- 限制引力波源的模型,包括中子星和黑洞.
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