Feedback Limits Rapid Growth of Seed Black Holes at High Redshift
Feedback Limits Rapid Growth of Seed Black Holes at High Redshift
复制标题
DOI：
10.1086/500557
复制
发表时间：
2005-12
期刊：
影响因子：
--
通讯作者：
Jian-Min Wang;Yan-Mei Chen;Chen Hu
中科院分区：
文献类型：
--
作者：
Jian-Min Wang;Yan-Mei Chen;Chen Hu
第三族恒星塌缩中形成的种子黑洞被用来解释高红移处超大质量黑洞的存在。有人建议，在红移 z = 20-24 时，通过高度超爱丁顿吸积约 106-107 年，种子黑洞可以生长到 105-106 M☉。我们研究了种子黑洞生长过程中辐射压、康普顿加热和流出的反馈。发现向种子孔提供燃料的其周围介质因康普顿加热而被大大加热。对于 103 M☉ 种子孔上的超临界吸积，康普顿球（温度约为 106 K）将在 1.6 × 103 年的时间尺度上形成，因此该孔仅由康普顿球爱丁顿极限的 10-3 速率提供。强流出的动力学反馈会加热距黑洞较远距离的介质；这导致黑洞外邦迪吸积量急剧减少，并避免了物质的积累。高超临界吸积将因强烈的反馈而迅速停止。除非能够避免强烈的反馈，否则种子黑洞在极早期的宇宙中很难长大。
Seed black holes formed in the collapse of Population III stars have been invoked to explain the presence of supermassive black holes at high redshift. It has been suggested that a seed black hole can grow up to 105-106 M☉ through highly super-Eddington accretion for a period of ~106-107 yr at redshift z = 20-24. We studied the feedback of radiation pressure, Compton heating, and outflow during the seed black hole growth. It is found that its surrounding medium fueled to the seed hole is greatly heated by Compton heating. For a supercritical accretion onto a 103 M☉ seed hole, a Compton sphere (with a temperature ~106 K) will be formed on a timescale of 1.6 × 103 yr so that the hole is only supplied by a rate of 10-3 of the Eddington limit from the Compton sphere. The kinetic feedback of the strong outflow will heat the medium at a large distance from the black hole; this leads to a dramatic decrease of the outer Bondi accretion onto the black hole and avoids the accumulation of the matter. The highly supercritical accretion will be rapidly halted by the strong feedback. The seed black hole hardly grows up at the very early universe unless the strong feedback can be avoided.