通过准周期性外流揭示了二进制黑洞系统的一个案例
Dheeraj R Pasham1, Francesco Tombesi2,3,4,5,6, Petra Suková7
1Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Science advances
|March 27, 2024
概括
研究人员从一个活跃的银河系核中发现了准周期性外流 (QPOuts),这表明一个中等质量的黑洞二进制. 这一发现为识别这种极端质量比二进制候选物提供了一种新的方法.
科学领域:
- 天体物理学 天体物理学
- 黑洞研究 黑洞研究
- 引力波天文学 引力波天文学
背景情况:
- 确定围绕超大质量黑洞运行的紧物体二进制系统对于理解引力波事件的前体至关重要.
- 这样的二进制星很难检测,阻碍了极端质量比的研究.
研究的目的:
- 为了研究在一个活跃的银河系核中观察到的X射线吸收的准周期变化的性质.
- 为了确定这种可变性是否可以通过一个包含超大质量黑洞和紧物体的二进制系统来解释.
主要方法:
- 在X射线吸收数据中分析准周期性变化.
- 排除基于观察到的属性的替代模型.
- 使用广义相对论磁动力学 (GRMHD) 模拟来建模观察到的现象.
主要成果:
- 观察到的准周期性变化被解释为准周期性外流 (QPOuts).
- 发生大约每8.3天一次的QPOuts与中等质量黑洞的二次性相一致.
- 据推测,二次黑洞位于与主要超大质量黑洞相距的~100重力半径的轻微偏心轨道上.
结论:
- 准周期性外流 (QPOuts) 为中间/极端质量比二元候选提供了一个新的观测特征.
- 这一发现为识别这些难以捉摸的系统提供了新的途径,这对于引力波研究至关重要.
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