Probing the early growth of supermassive black holes with the environment of high-redshift quasars

用高红移类星体环境探索超大质量黑洞的早期生长

• 批准号: 19J11013
• 负责人: 何 晩秋
• 金额: $ 1.09万
• 依托单位: National Astronomical Observatory of Japan
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2019
• 资助国家: 日本
• 起止时间: 2019-04-25 至 2021-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-19J11013/
• 关键词: AGN; high-z universe

This work aims at probing the early growth of supermassive black holes in the early universe. Supermassive black holes, which can be over millions of solar masses, are found to be ubiquitous at the center of local massive galaxies, like our Milky Way. How are these monsters formed and evolved? Theoretical works suggest two possible origins: a heavy black hole seed or a typical stellar-mass black hole seed with powerful growth.In this work, thanks to the wide and deep imaging of the Hyper Suprime-Cam Subaru Strategic Program, we constructed a large sample of quasars (i.e., rapidly growing supermassive black holes) over a wide luminosity range at redshift 4 (around 1.5 Gyr after the BigBang). Compared to previous works, this work extends the magnitude coverage of quasar sample towards the deep end by over 2 order of magnitude. The wide magnitude range makes our quasar sample more numerous, and it can provide less-biased view on early growth of supermassive black holes.We estimated their black hole mass and Eddington ratio (which can be used to quantify accretion rate) using Keck/DEIMOS and AAT/AAOmega spectrograph. In this fiscal year, we utilized the information to trace back their possible growth tracks. Results suggest 1) those quasars need a heavy black hole seed to be formed even under the extreme growing mode; and 2) those quasars are tending to "shut-down" their vigorous growth to episodic growth afterwards.

这项工作旨在探讨早期宇宙中超质量黑洞的早期增长。超过数百万个太阳能大块的超质量黑洞被发现在当地大型星系的中心无处不在，例如我们的银河系。这些怪物如何形成和发展？理论作品提出了两个可能的起源：一个重的黑洞种子或典型的恒星质量黑洞种子，具有强大的生长。在这项工作中，得益于超级Soprime-Cam Subaru策略性计划的广泛而深层的成像，我们在Redshift 4（大约1.5 gyr）（大约在Redshift 4 ground groun flos of Redshift范围内）构建了大量的类星体样本（即，快速增长的超级黑洞）。与以前的工作相比，这项工作将类星体样品的幅度扩展到深端的幅度范围以上超过2个数量级。较大的范围使我们的类星体样品越来越多，并且可以使用Keck/Deimos和AAT/AAOOMEGA频谱仪估计其黑洞质量和爱丁顿的比例（可用于量化增生率）。在这个财政年度，我们利用这些信息来追溯他们可能的增长轨道。结果表明1）即使在极端生长的模式下，这些类星体也需要形成重的黑洞种子； 2）这些类星体倾向于“关闭”其剧烈的增长，以使情节增长。

项目成果

Black hole mass and Eddington ratio distributions of the z=4 less-luminous quasars over the HSC Wide field

HSC 宽视场上 z=4 亮度较低的类星体的黑洞质量和爱丁顿比分布

• 发表时间: 2021
• 作者: 大橋完太郎;トーマス・ブルック;Griseldis Kirsch;久山雄甫;奥堀亜紀子;尾田知子;筒井瑞貴;中村紀彦;林玲穂;Wanqiu He
• 通讯作者: Wanqiu He