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活跃的银河系核作为缩放的银河系黑洞
I M McHardy1, E Koerding, C Knigge
1School of Physics and Astronomy, The University, Southampton SO17 1BJ, UK. imh@astro.soton.ac.uk
Nature
|December 8, 2006
概括
活跃的银河系核 (AGN) 行为像扩大规模的银河系黑洞系统. 这一基于X射线变化和光学发射线的发现证实,在不同黑洞质量之间,积累过程是一致的.
科学领域:
- 天体物理学 天体物理学
- 黑洞物理学 黑洞物理学
- 太空进化的宇宙进化
背景情况:
- 天体物理学中的一个关键问题是,活动银河核 (AGN) 在按质量缩小时是否表现出与银河黑洞系统相似的变化模式.
- 来自黑洞附近的X射线辐射是理解黑洞行为的关键诊断.
研究的目的:
- 通过比较它们的X射线变化时间尺度来确定AGN是否基本上是银河系黑洞的缩放版本.
- 为了在两种类型的黑洞系统中的积累过程之间建立物理联系.
主要方法:
- 从AGN和银河黑洞系统的X射线变化中分析特征时间尺度.
- 为增加率变化进行校正,以便直接比较时间表.
- 在AGN中光学发射线宽度与它们特有的X射线时间尺度之间的相关性分析.
主要成果:
- 考虑到积累速率的变化后,从AGN和银河黑洞的X射线变化时间尺度被发现是物理相关的.
- 证明积累过程对于小 (银河系) 和大 (AGN) 黑洞都是一致的.
- 在AGN中光学发射线的宽度与它们特有的X射线时间尺度之间观察到强烈的相关性,支持了这种联系.
结论:
- 活跃的银河系核 (AGN) 已被证实是银河系黑洞系统的缩放版本.
- 控制小型黑洞和超大质量黑洞的积累物理学基本上是一样的.
- 这种统一的理解允许通过观察银河系系统在宇宙时间尺度上研究AGN行为.
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