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在红移5.8-6.6时通过强烈的外流抑制黑洞的生长
M Bischetti1, C Feruglio2,3, V D'Odorico2,3,4
1INAF - Osservatorio Astronomico di Trieste, Trieste, Italy. manuela.bischetti@inaf.it.
Nature
|May 13, 2022
概括
早期超大质量黑洞的强大风阻碍了它们的生长. 这些在早期宇宙中观察到的类星体外流表明了黑洞反机制的开始.
科学领域:
- 宇宙的演化
- 天体物理学
- 黑洞物理
背景情况:
- 由超大质量黑洞驱动的明亮类星体存在于再电离时代 (大爆炸后的50亿到100亿年).
- 这些早期黑洞的快速形成及其质量超过局部相关性仍然存在争议.
- 黑洞生长调节的机制和时间尚不清楚,尽管黑洞反是可疑的驱动因素.
研究的目的:
- 在早期宇宙中调节超大质量黑洞生长的过程.
- 确定黑洞反机制的开始和特征.
- 了解从快速早期增长到本地宇宙中观察到的共生增长的过渡.
主要方法:
- 在5.8至6.6红移的光学和近红外观测.
- 频谱分析以确定广泛的,蓝色移动的吸收线底部,表明流出.
- 较低红移 (z ≈ 2-4) 的类星体的外流特性比较.
主要成果:
- 大约一半的观测到的类星体在z 5.8处呈现出广的蓝移吸收低谷.
- 这些特征表明黑洞驱动的风流速度极高,
- 与z ≈ 2-4相比,具有这种外流风的类星体的比例大约是z ≈ 5.8的2.4倍.
结论:
- 在z 5.8的外流将大量能量注入星际介质,抑制核气体积聚,并减缓黑洞的增长.
- 这可能标志着黑洞反的开始.
- 这些外流类星体的红色光学颜色和灰尘性质表明它们处于暗积和灭的初始阶段.
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