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一个可能的密切的超大质量黑洞二进制星体在一个具有光学周期性的类星体中
Matthew J Graham1, S G Djorgovski1, Daniel Stern2
1California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, USA.
Nature
|January 7, 2015
概括
天文学家在类星体PG 1302-102的光线中发现了一种重复的模式,这表明超大质量黑洞的二进制系统. 这一发现为银河系进化和这些巨大的物体的形成提供了新的见解.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
背景情况:
- 类星体以它们在所有波长的变化而闻名.
- 类星体的光学变异性通常是随机的,通常被模拟为一个缓和的随机步行.
- 大规模的天文时间序列数据集现在可以对类星体变异性进行系统研究.
研究的目的:
- 用广泛的时间序列数据系统地探索类星体变异性.
- 为了识别类星体光学光曲线内的周期信号.
主要方法:
- 分析了来自247,000个光谱证实类星的光曲线.
- 在9年的时间基线上进行了周期性变异的搜索.
- 利用统计方法来识别重要的周期信号.
主要成果:
- 在类星体PG 1302-102的光学可变性中检测到强烈,光滑的周期信号.
- 观察到的信号周期为1884±88天.
- 这种周期信号在一个大数据集中发现了类星体光曲线.
结论:
- 对观察到的周期性最合理的解释是两个超大质量黑洞的二进制系统,其间隔为亚分秒.
- 这样的二进制黑洞系统是星系合并的预期结果.
- 这一发现可以为星系形成和演化模型提供关键的约束.
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