在BL Lacertae的相对论喷流中的快速准周期性振荡
S G Jorstad1,2, A P Marscher3, C M Raiteri4
1Institute for Astrophysical Research, Boston University, Boston, MA, USA. jorstad@bu.edu.
Nature
|September 7, 2022
概括
在2020年爆发期间,在BL Lacertae星体中观察到短期准周期性振荡 (QPOs). 这些罕见的,快速的QPOs可能由电流驱动的扭曲不稳定性来解释.
科学领域:
- * 天体物理学
- * 高能天体物理学
- * 银河系外的天文学
背景情况:
- * 黑星,是一种活跃的星系核 (AGN),表现出来自相对论喷射的高度可变的非热辐射.
- 在AGN中,近周期性振荡 (QPOs) 是罕见的,特别是那些具有短时间 (小时到天) 的振荡,它们的起源受到争议.
- * BL Lacertae (BL Lac) 是一个由超大质量黑洞驱动的原型星体.
研究的目的:
- * 为了研究在Blazar喷射中罕见的,短时间的QPO的性质.
- * 分析2020年重大爆发期间BL Lacertae的变异性.
- * 在AGN喷气中测试QPO生成的理论模型.
主要方法:
- * 对BL Lacertae进行强烈的光学和马射线流量监测.
- * 光学线性偏振数据的分析.
- * 观察到的QPO与理论模型的相关性.
主要成果:
- 在2020年爆发期间,BL Lacertae的光流,线性极化和马射线流中发现了QPO.
- * 观察到的QPO周期约为13小时.
- * 观测到的QPO的属性与在回调冲击附近的电流驱动的扭曲不稳定性的预测一致.
结论:
- 在BL Lacertae中观察到的短期QPOs支持AGN喷气中电流驱动的扭曲不稳定性模型.
- * 这些发现提供了喷气不稳定的证据, 发生在距离黑洞大约5个帕塞克的重定位冲击附近.
- 这项研究提供了对驱动布拉扎尔变异的物理过程的见解.
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