arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1602.01941astro-ph.GAastro-ph.COastro-ph.HE
收藏

Horizon-AGN模拟中大质量黑洞的宇宙演化

The cosmic evolution of massive black holes in the Horizon-AGN simulation

Marta Volonteri, Yohan Dubois, Christophe Pichon, Julien Devriendt

摘要:

我们分析了大体积宇宙流体动力学模拟Horizon-AGN中黑洞的人口统计学特征。这个模拟统计模型有多少气体被吸积到BH上,跟踪沉积到它们的环境中的能量,因此,环境介质对BH生长的反反应。合成BH再现了各种观测的限制,如红移的BH质量密度和质量函数的演变。通过AGN反馈的强自我调节,弱超新星反馈,和未解决的内部过程导致紧密的BH星系质量相关。从z~2开始,潮汐剥离产生了一小部分相对于晕质量过大的黑洞。拥有中心黑洞或活动星系核的星系比例随着恒星质量的增加而增加。活动星系核的分数同意更好地与多波长的研究,比单波长的,除非考虑到遮蔽。最大的晕呈现BH多重性,通过正在进行的或过去的合并获得额外的BH。在某些情况下,中心和偏离中心的活动星系核同时发光,产生双重活动星系核。正如观测中所发现的那样,这种双重活动星系核的数量随着红移的减小而减少。比吸积率和爱丁顿比分布与观测估计吻合得很好。BH人口依次由快,慢,和非常慢的吸积器占主导地位,分别在z=3和z=2处发生转变。

英文摘要:

We analyse the demographics of black holes (BHs) in the large-volume cosmological hydrodynamical simulation Horizon-AGN. This simulation statistically models how much gas is accreted onto BHs, traces the energy deposited into their environment and, consequently, the back-reaction of the ambient medium on BH growth. The synthetic BHs reproduce a variety of observational constraints such as the redshift evolution of the BH mass density and the mass function. Strong self-regulation via AGN feedback, weak supernova feedback, and unresolved internal processes result in a tight BH-galaxy mass correlation. Starting at z~2, tidal stripping creates a small population of BHs over-massive with respect to the halo. The fraction of galaxies hosting a central BH or an AGN increases with stellar mass. The AGN fraction agrees better with multi-wavelength studies, than single-wavelength ones, unless obscuration is taken into account. The most massive halos present BH multiplicity, with additional BHs gained by ongoing or past mergers. In some cases, both a central and an off-centre AGN shine concurrently, producing a dual AGN. This dual AGN population dwindles with decreasing redshift, as found in observations. Specific accretion rate and Eddington ratio distributions are in good agreement with observational estimates. The BH population is dominated in turn by fast, slow, and very slow accretors, with transitions occurring at z=3 and z=2 respectively.

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。

↑