arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1802.07264astro-ph.GAastro-ph.CO
收藏

流angular momentum和辐射反馈联合作用下黑洞的阻塞吸积生长

Stunted accretion growth of black holes by combined effect of the flow angular momentum and radiation feedback

Kazuyuki Sugimura, Takashi Hosokawa, Hidenobu Yajima, Kohei Inayoshi, Kazuyuki Omukai

摘要:

吸积到种子黑洞(BH)上被认为在高红移(z>6)观测到的超大质量黑洞的形成中起着至关重要的作用。在这里,我们调查的气体角动量和辐射反馈的吸积流的综合效果,通过执行二维轴对称辐射流体动力学模拟,同时解决整个邦迪半径和吸积盘的外部的流动结构。具有有限角动量的吸积气体在Bondi半径内形成旋转支撑的盘,其中由于假定的α型粘度,吸积通过角动量输运进行。我们发现,辐射和角动量的相互作用显着抑制吸积,即使在赤道阴影区的辐射反馈减弱。吸积速率是O(alpha)\sim O(0.01-0.1)乘以Bondi值,其中alpha是粘度参数。通过发展一个分析模型,我们表明,这样一个巨大的减少吸积率持续,除非角动量是如此之小,相应的离心半径是\lesssim 0.04倍的邦迪半径。我们认为,考虑到本文提出的角动量势垒,黑洞很难通过快速质量吸积快速增长。

英文摘要:

Accretion on to seed black holes (BHs) is believed to play a crucial role in formation of supermassive BHs observed at high-redshift (z>6). Here, we investigate the combined effect of gas angular momentum and radiation feedback on the accretion flow, by performing 2D axially symmetric radiation hydrodynamics simulations that solve the flow structure across the Bondi radius and the outer part of the accretion disc simultaneously. The accreting gas with finite angular momentum forms a rotationally-supported disc inside the Bondi radius, where the accretion proceeds by the angular momentum transport due to assumed alpha-type viscosity. We find that the interplay of radiation and angular momentum significantly suppresses accretion even if the radiative feedback is weakened in an equatorial shadowing region. The accretion rate is O(alpha)\sim O(0.01-0.1) times the Bondi value, where alpha is the viscosity parameter. By developing an analytical model, we show that such a great reduction of the accretion rate persists unless the angular momentum is so small that the corresponding centrifugal radius is \lesssim 0.04 times the Bondi radius. We argue that BHs are hard to grow quickly via rapid mass accretion considering the angular momentum barrier presented in this paper.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑