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一个8亿太阳质量的黑洞在显著中立的宇宙中,红移7.5
Eduardo Bañados1, Bram P Venemans2, Chiara Mazzucchelli2
1The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, California 91101, USA.
Nature
|December 7, 2017
概括
天文学家发现了一个类星体, J1342+0928, 红移7.54, 提供了关于早期宇宙黑洞增长的见解. 这一发现表明在再电离时代出现了快速的黑洞形成或超大质量黑洞.
科学领域:
- 宇宙学
- 天体物理学
- 黑洞物理
背景情况:
- 类星体是宇宙中最明亮的物体, 能够研究早期的宇宙.
- 超过五年来,ULAS J1120+0641是唯一已知的红移z>7的类星体,这限制了早期宇宙研究.
- 了解早期宇宙中超大质量黑洞的形成和生长仍然是一个关键挑战.
研究的目的:
- 报告发现和描述一个新的类星体在一个记录红移.
- 在早期宇宙中研究超大质量黑洞的生长.
- 在再电离时代探测星际介质中的中性分数.
主要方法:
- 在红移z=7.54时对类星体ULAS J134208.10+092838.61 (J1342+0928) 的观测.
- 分析类星体的光度和黑洞质量.
- 进行光谱分析以检测Gunn-Peterson阻尼翼并推断中性分数.
主要成果:
- 发现了J1342+0928,一个位于z=7.54的类星体,其极度亮度是太阳的4×10^13倍.
- 估计黑洞质量为8×10^8太阳质量,当时宇宙只有6.9亿年.
- 在银河间介质中存在显著的中性 (在68%的概率下>33%) 的证据,由Gunn-Peterson缓冲翼表示.
结论:
- J1342+0928的存在挑战了早期的黑洞生长模型,支持了巨大的初始黑洞种子或超埃丁顿积累的理论.
- 量子星的光谱表明宇宙在这个时代显著中立, 证实我们正在探测再电离时代.
- 这一发现为了解早期宇宙中星系和超大质量黑洞的共同进化提供了关键的观测数据.
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