Black hole mergers in active galactic nuclei

活跃星系核中的黑洞合并

• 批准号: 2444181
• 金额: --
• 依托单位: University of Oxford
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2020
• 资助国家: 英国
• 起止时间: 2020 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2444181
• 关键词: Black; hole; mergers; active; galactic

This research falls within the RC's Particle Astrophysics Gravitational Waves research area. The recent detections of gravitational waves by LIGO, VIRGO, and KAGRA opened a new window on the Universe, giving unprecedented observational opportunities into regions of space and time which are completely hidden to traditional electromagnetic observatories. The gravitational wave detections have shown that stellar mass black holes merge frequently in the Universe, but the astrophysical origin and host environments of these mergers is not well understood. The objective of the project is to examine a novel possibility that may explain the gravitational wave observations. We examine the possibility that the observed stellar mass black hole mergers originate in active galactic nuclei in the vicinity of a supermassive black hole. We build numerical models of the gaseous disk surrounding a supermassive black hole and investigate how a population of stellar mass black holes in this region interact within the disk. We investigate the possibility that black holes form binaries during close encounters, and dynamical interaction of such binaries with other stars and black holes. The interplay of hydrodynamical and gravitational wave effects may lead to an efficient merger of black holes in these environments. We determine the expected rate of mergers and the characteristics of the gravitational waves from these systems, and compare the predictions of these theoretical models with the observed source population of LIGO, VIRGO, and KAGRA. We will also explore the expected implications for the LISA space mission.The potential impact of this research is not limited to gravitational wave science but it may have applications in cosmology and planet formation. Black hole mergers in active galactic nuclei generate gravitational wave events with possible electromagnetic counterparts. If so, these sources make it possible to use them as standard candles to probe the cosmological model of the Universe. Furthermore, the dynamics of point masses in gaseous environments may also be relevant to understand the evolution of planetesimals in protoplanetary disks. The numerical methodology and theoretical framework developed for this project may be applied in the context of planet formation as well.

这项研究属于RC的粒子天体物理引力波研究区域。 Ligo，处女座和Kagra对重力波的最新检测为宇宙打开了一个新窗口，从而使前所未有的观测机会完全隐藏在传统的电磁观测器中。引力波检测表明，宇宙中经常合并恒星的质量黑洞，但是这些合并的天体物理起源和宿主环境尚不清楚。该项目的目的是检查一种新的可能性，可以解释引力波观测。我们研究了观察到的恒星质量黑洞合并起源于超级质量黑洞附近的活性银河核。我们构建了围绕超级黑洞的气态磁盘的数值模型，并研究了该地区恒星质量黑洞的种群如何在磁盘中相互作用。我们调查了在紧密相遇中形成二进制的可能性，以及这种二进制文件与其他恒星和黑洞的动态相互作用。流体动力学和重力波效应的相互作用可能导致在这些环境中有效合并黑洞。我们确定了从这些系统中确定合并的预期速率和重力波的特征，并将这些理论模型的预测与观察到的Ligo，Wirgo和Kagra的源群体进行了比较。我们还将探讨对丽莎太空任务的预期影响。这项研究的潜在影响不限于引力科学，而是在宇宙学和行星形成中有应用。活性银核中的黑洞合并与可能的电磁对应物产生重力波事件。如果是这样，这些来源将可以将它们用作标准蜡烛来探测宇宙的宇宙学模型。此外，气态环境中点质量的动力学也可能与理解原星磁盘中行星的演变有关。为该项目开发的数值方法和理论框架也可以在行星形成的背景下应用。