The first quasars and super-massive black holes

第一个类星体和超大质量黑洞

• 批准号: 2275457
• 金额: --
• 依托单位: Imperial College London
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2275457
• 关键词: first; quasars; super; massive; black

A quasar, the glowing disk of gas around the super-massive black hole at the centre of a galaxy, can be hundreds of times more luminous than its host galaxy, and the brightest quasars are the most powerful non-transient objects in the Universe. Quasars have been discovered when the Universe was just 5% of its current age (of 13.8 billion years) and represent the only way to trace the formation of the first super-massive black holes. The first part of this project would be to use the results from surveys of distant quasars to determine their properties as a population and, in particular, how it is evolving with cosmic time. This will involve a combination of modelling and Bayesian inference to combine the results of very different samples, hence aiding the design of future surveys that aim to push to even greater distances. The second part of this project concerns the black holes themselves: it is very difficult to explain the formation of black holes of > 10^9 Solar masses in less than a billion years, but another possibility is that they are not actually so massive - their mass estimates come from extrapolating an imperfect empirical correlation established from a different population of quasars which, typically, have much lower mass black holes, and the current approaches to this problem tend to ignore the various sources of uncertainty. In this project we will go back to the original data and establish what can really be said about the first super-massive black holes and quasars and their formation mechanisms.

类星体是星系中心超大质量黑洞周围的发光气体盘，其亮度比其宿主星系高数百倍，而最亮的类星体是宇宙中最强大的非瞬态天体。类星体是在宇宙年龄仅为当前年龄（138 亿年）5% 时被发现的，并且是追踪第一个超大质量黑洞形成的唯一方法。该项目的第一部分是利用对遥远类星体的调查结果来确定它们作为群体的属性，特别是它如何随宇宙时间演化。这将涉及建模和贝叶斯推理的结合，以结合非常不同的样本的结果，从而有助于设计未来的调查，旨在推动更远的距离。该项目的第二部分涉及黑洞本身：很难解释在不到 10 亿年的时间内形成> 10^9 太阳质量的黑洞，但另一种可能性是它们实际上并没有那么大 - 它们的质量估计来自于对不同类星体群体建立的不完美经验相关性的推断，这些类星体通常具有低得多的质量黑洞，而当前解决此问题的方法往往忽略了各种不确定性来源。在这个项目中，我们将回到原始数据，并确定关于第一个超大质量黑洞和类星体及其形成机制的真正内容。