在黑洞X射线二进制星系的爆发中追踪到强大的磁盘风
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
概括
黑洞二进制中的积聚盘粘度 (α) 使用爆发光曲线进行估计. 高的α值表明有效的角动量传输或通过潜在的磁力驱动的输出流显著的质量损失.
科学领域:
- 天体物理学与天文学
- 恒星进化和紧物体
- 等离子体物理和磁动力学
背景情况:
- 在紧的恒星残留物 (黑洞,中子星,白矮星) 上的积聚驱动着爆发,为积聚物理提供了洞察力.
- 由粘度参数α量化的积累盘的角运动量转移形成了爆发光曲线.
- 之前的研究估计了白矮星的α值,而不是黑洞或中子星系统的α值.
研究的目的:
- 使用观测数据估计黑洞周围积聚盘的粘度参数 (α).
- 研究黑洞积累盘中驱动角动量传输和质量损失的物理机制.
- 在黑洞X射线二进制中区分磁力驱动的流出和热力驱动的风.
主要方法:
- 对黑洞X射线二进制星系21次爆发的X射线光线曲线进行分析.
- 将贝叶斯方法应用于积累模型以确定粘度参数 (α).
- 估计的α值与二进制数据的积累状态之间的相关性分析.
主要成果:
- 黑洞积聚盘的估计粘度参数 (α) 从0.2到1.0不等,远高于以前发现的白矮星.
- 高的α值与高效的角动量传输或通过外流的大量质量损失一致.
- 估计的α和积累状态之间没有发现相关性,这表明所有状态都有外流.
结论:
- 黑洞积聚盘中的高粘度可能由磁旋不稳定性与大规模磁场维持.
- 显著的磁盘外流可能是形成爆发的原因,去除了很大一部分磁盘质量.
- 观察到的行为表明磁驱动的磁盘风而不是热驱动的磁盘风,独立于特定的辐射条件.
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