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有读书笔记Black hole growth in the early Universe is self-regulated and largely hidden from view

唐唐 添加于 2011-6-21 05:05 | 1904 次阅读 | 0 个评论
  •  作 者

    Treister E, Schawinski K, Volonteri M, Natarajan P, Gawiser E
  •  摘 要

    The formation of the first massive objects in the infant Universe remains impossible to observe directly and yet it sets the stage for the subsequent evolution of galaxies1, 2, 3. Although some black holes with masses more than 109 times that of the Sun have been detected in luminous quasars less than one billion years after the Big Bang4, 5, these individual extreme objects have limited utility in constraining the channels of formation of the earliest black holes; this is because the initial conditions of black hole seed properties are quickly erased during the growth process6. Here we report a measurement of the amount of black hole growth in galaxies at redshift z = 6–8 (0.95–0.7 billion years after the Big Bang), based on optimally stacked, archival X-ray observations. Our results imply that black holes grow in tandem with their host galaxies throughout cosmic history, starting from the earliest times. We find that most copiously accreting black holes at these epochs are buried in significant amounts of gas and dust that absorb most radiation except for the highest-energy X-rays. This suggests that black holes grew significantly more during these early bursts than was previously thought, but because of the obscuration of their ultraviolet emission they did not contribute to the re-ionization of the Universe.
  •  详细资料

    • 文献种类:期刊
    • 期刊名称: Nature
    • 期刊缩写: Nature
    • 期卷页: 2011  474 7351 356-358
    • ISBN: 0028-0836
  • 相关链接 DOI URL 

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    天文学家观测到宇宙早期黑洞
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