活跃星系核的强烈长期变异性影响病毒黑洞质量测量
Neelesh Amrutha1, Christian Wolf2,3, Christopher A Onken2,3
1Research School of Astronomy and Astrophysics, Australian National University, Canberra, ACT, Australia. neelesh.amrutha@anu.edu.au.
Nature communications
|February 5, 2026
概括
活跃银河系核 (AGN) 超大质量黑洞的质量估计在使用狭窄的[OIII]发射线亮度来确定广泛的发射线区域大小时,在20年内更容易重复.
科学领域:
- 天文学和天体物理学
- 宇宙学的宇宙学是什么?
- 天体物理学 天体物理学
背景情况:
- 活跃的银河系核 (AGN) 拥有快速增长的超大质量黑洞.
- 超大质量黑洞的质量通常使用广发射线区域 (BLR) 气体运动和AGN亮度来估计.
- "呼吸BLR"模型预测BLR尺寸的变化与亮度,影响质量估计.
研究的目的:
- 通过在20年内观察AGN来测试"呼吸BLR"模型.
- 调查BLR大小的长期稳定性及其对黑洞质量估计的影响.
- 确定可靠的方法来估计黑洞在AGN中的质量.
主要方法:
- 在20年间隔的两个时代中观察一个红移小于0.1的AGN样本.
- 分析光谱线宽度和观测之间的AGN亮度变化.
- 比较从不同的方法中得出的质量估计,包括使用狭窄[OIII]排放线发光度的方法.
主要成果:
- 在20年内,AGN发光度和衍生黑洞质量估计变化了2倍,显示了平均逆转.
- 观察到的光谱线宽度保持不变,与"呼吸BLR"模型对尺寸变化的预测相矛盾.
- 使用狭窄的[OIII]排放线亮度估计BLR大小,在20年期间产生了最可重复的质量测量.
结论:
- 在AGN中的宽发射线区域在亮度变化期间似乎不会显著改变尺寸.
- 恒定线宽支持BLR大小是稳定的想法,解释了对瞬间爱丁顿比率的依赖.
- 用BLR大小的狭窄[OIII]发光度估计黑洞质量,可以在长时间内进行最稳健和可重复的测量.
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