Investigating evidence for different black hole accretion modes since redshift z~1
A. Georgakakis, P. G. Pérez-González, N. Fanidakis, M. Salvato, J. Aird, H. Messias, J. M. Lotz, G. Barro, Li-Ting Hsu, K. Nandra, D. Rosario, M. C. Cooper, D. … 展开作者
A. Georgakakis, P. G. Pérez-González, N. Fanidakis, M. Salvato, J. Aird, H. Messias, J. M. Lotz, G. Barro, Li-Ting Hsu, K. Nandra, D. Rosario, M. C. Cooper, D. D. Kocevski, J. A. Newman
本文将COSMOS、AEGIS-XD和4 Ms CDFS的Chandra数据与光学/近红外测光相结合，确定了活动星系核（AGN）X射线寄主在平均红移0.40和0.85处的静止坐标系U-V和V-J色。这种颜色的组合（UVJ）提供了一种有效的方法来区分静止星系和恒星形成星系，包括尘埃变红的星系。形态信息强调了活动星系核之间的差异分裂的UVJ的颜色。静止星系中的活动星系核主要由球状体组成，而恒星形成的宿主则分为凸起和盘状。AGN主机的UVJ图，然后用来设定与演化和恒星形成系统的吸积密度的限制。自z~1以来，大部分黑洞的增长都与恒星形成的宿主有关。然而，从z~1开始，X射线光度密度的~15-20%发生在UVJ图的静止区域。对于z~0.40的子样本，有初步的证据（2sigma显著性），活动星系核分裂的UVJ颜色不同的爱丁顿比。活动星系核在恒星形成的主机占主导地位，在高爱丁顿比，而活动星系核在静止的主机变得越来越重要，作为总人口的一部分，对低爱丁顿比。在较高的红移z~0.8时，这种差异仅在爱丁顿比> 1 e-3时才在2 σ水平上显著。这些发现与不同的吸积模式负责在星系中心建立SMBHs的情景是一致的。我们比较了我们的结果与GALFORM半解析模型，其中假定两个黑洞燃料模式，第一个链接到恒星形成和第二发生在被动星系。与数据相比，GALFORM预测在z<1的静止星系中黑洞增长的比例更大。放松模型中被动活动星系核宿主恒星形成率为零的强假设可以调和这种分歧。
英文摘要：
Chandra data in the COSMOS, AEGIS-XD and 4Ms CDFS are combined with optical/near-IR photometry to determine the rest-frame U-V vs V-J colours of X-ray AGN hosts at mean redshifts 0.40 and 0.85. This combination of colours (UVJ) provides an efficient means of separating quiescent from star-forming, including dust reddened, galaxies. Morphological information emphasises differences between AGN split by their UVJ colours. AGN in quiescent galaxies are dominated by spheroids, while star-forming hosts are split between bulges and disks. The UVJ diagram of AGN hosts is then used to set limits on the accretion density associated with evolved and star-forming systems. Most of the black hole growth since z~1 is associated with star-forming hosts. Nevertheless, ~15-20% of the X-ray luminosity density since z~1, is taking place in the quiescent region of the UVJ diagram. For the z~0.40 subsample, there is tentative evidence (2sigma significance), that AGN split by their UVJ colours differ in Eddington ratio. AGN in star-forming hosts dominate at high Eddington ratios, while AGN in quiescent hosts become increasingly important as a fraction of the total population toward low Eddington ratios. At higher redshift, z~0.8, such differences are significant at the 2sigma level only at Eddington ratios >1e-3. These findings are consistent with scenarios in which diverse accretion modes are responsible for the build-up of SMBHs at the centres of galaxies. We compare our results with the GALFORM semi-analytic model, which postulates two black hole fuelling modes, the first linked to star-formation and the second occuring in passive galaxies. GALFORM predicts a larger fraction of black hole growth in quiescent galaxies at z<1, compared to the data. Relaxing the strong assumption of the model that passive AGN hosts have zero star-formation rate could reconcile this disagreement.
Low-redshift absorption in the Seyfert galaxy PG 1211+143 -- a distant inflow maintaining off-plane accretion or the gravitational redshift of matter orbiting the SMBH?
The possible accretion discs of GN-z11 at redshift z = 10.6, MoM-z14 at z = 14.44 and other high redshift objects
University of Warwick（华威大学）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Kavli Institute for Cosmology, University of Cambridge（剑桥大学卡弗里宇宙学研究所）；Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪许实验室）；Department of Physics and Astronomy, University College London（伦敦大学学院物理与天文系）；Institute of Astronomy, University of Cambridge（剑桥大学天文学研究所）
Peculiar black hole accretion rates in AGN with highest star formation rates in the universe
Pouliasis et al（2022 b）研究了恒星形成率、黑洞吸积率和红移大于3.5的活动星系的恒星质量，发现恒星形成率在高恒星质量时趋于平稳，他们认为这是活动星系核反馈的证据。他们的数据显示，当活动星系核接近恒星形成率-恒星质量平面曲线的平坦化时，吸积率开始下降。我们描述的活动星系核反馈的性质负责这方面的强大FRII喷气机提高恒星形成率，但最终也引发了吸积从近爱丁顿率平流为主的转变。这些系统正处于一个戏剧性的转变的风口浪尖上，活动星系从强烈的增强到对恒星形成的巨大抑制，在这种方式下，与高红移的射电活动星系核和无喷流的活动星系核相比，低红移的射电活动星系核的斜率更陡。因此，我们认为，Pouliasis等人的数据构成了Singh等人（2021）预测的高红移天体，这些天体与Comerford等人（2020）所示的射电活动星系核的低红移行为有关。
Cosmological 21cm line observations to test scenarios of super-Eddington accretion on to black holes being seeds of high-redshifted supermassive black holes
