The evolution of the dynamics and chemistry of star forming galaxies across cosmic time

整个宇宙时间恒星形成星系的动力学和化学演化

• 批准号: 2711100
• 金额: --
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2022
• 资助国家: 英国
• 起止时间: 2022 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2711100
• 关键词: evolution; dynamics; chemistry; star; forming

The Hubble-Sequence of galaxy morphologies remains one of the defining characteristics of galaxies, and provides one of the key constraints that galaxy formation models strive to reproduce. Dynamical studies of local galaxies have shown that the Hubble Sequence of galaxy morphologies follows a sequence of increasing angular momentum at a fixed mass. In the cold dark matter paradigm, galaxies form at the centres of dark matter halos. As the gas collapses within the dark halo, the baryons can both lose and gain angular momentum. If the angular momentum of the baryons is (weakly) conserved during collapse, they will form a centrifugally supported disk with an exponential light profile (e.g. a spiral galaxy). If the angular momentum is redistributed (due to mergers and/or strong outflows), the morphology of the galaxy is more likely to represent a early-type or elliptical galaxy. While the role of angular momentum in locating galaxies along the Hubble-Sequence is well constrained at z=0, how the baryonic angular momentum evolves with cosmic time, and results in the emergence of the Hubble-Sequence at high redshift has not been established. Observations from the Hubble Space Telescope (HST) have shown that the transition from a galaxy population dominated by clumpy, irregular morphologies to smoother, disk-like galaxies appears to occur around z=1.5, and this has been heralded as the epoch when the Hubble Sequence "emerged", In this project, we will conduct an observational program to measure the gas properties and star formation properties in a sample of galaxies at z=1-3 (i.e. lookback times of 7-10 billion years). We will measure the role of baryons, dark matter, disk turbulence, and gas inflows and outflows in defining the formation of the galaxies. We will address the following inter-related questions: 1. How does the angular momentum of high-redshift galaxy disks result in the emergence of the Hubble-Sequence? 2. How do the dark matter fractions of galaxies evolve with mass and redshift? 3. What physical processes control the formation and evolution of star-forming regions and the gas disk? 4. Where do star-forming winds originate and how much mass and angular momentum do they carry? This is an observationally-driven PhD project. The successful student will use a range of observational facilities, potentially including travel to Chile, Hawaii or Europe to obtain data for their thesis. The PhD will provide training in the reduction and analysis of imaging, integral field spectroscopy and interferometry There will also be opportunities to relate the observational results to theoretical models being developed at Durham.

星系形态的哈勃序列仍然是星系的定义特征之一，并提供了银河形成模型努力繁殖的关键约束之一。局部星系的动态研究表明，星系形态的哈勃序列遵循在固定质量下增加角动量的序列。在冷暗物质范式中，暗物质光环中心形成星系。随着气体在黑暗的光环中崩溃时，重子既可以失去并获得角动量。如果巴元的角动量在塌陷期间（弱）保守，则它们将形成具有指数光谱的离心磁盘（例如螺旋星系）。如果将角动量重新分布（由于合并和/或强大的流出引起），则银河系的形态更有可能代表早期型或椭圆形的星系。尽管角动量在沿着哈勃序列定位星系中的作用在z = 0处得到很好的约束，但尚未确定重质角动量随宇宙时间的发展，并导致高返带时哈勃序列的出现。来自哈勃太空望远镜（HST）的观察结果表明，从一个由块状，不规则形态主导的星系群体到Z = 1.5左右发生的磁盘状星系的过渡似乎是在Z = 1.5左右发生的，并且在此期间，该图案又可以衡量“ Emerventional”的属性，以衡量的属性，我们会衡量型号，以衡量型号的属性，以衡量型号的效率，以验证一个型号，以衡量型号的范围，以衡量型号的范围，以衡量型号的性能，并介绍了一个型号的范围，并且在范围内构成了一个型号。 Z = 1-3的星系（即回顾时间为7-100亿年）。我们将衡量重子，暗物质，磁盘湍流以及气体流入和流出在定义星系形成中的作用。我们将解决以下相互关联的问题：1。高红移星系磁盘的角动量如何导致哈勃序列的出现？ 2。星系的暗物质分数如何随质量和红移而发展？ 3.哪些物理过程控制恒星形成区域和气盘的形成和演变？ 4。恒星形成的风在哪里起源，它们携带多少质量和角动量？这是一个以观察为驱动的博士学位项目。成功的学生将使用一系列观察设施，包括前往智利，夏威夷或欧洲的旅行以获取其论文数据。博士将提供培训，以减少和分析成像，整体场光谱和干涉法，也将有机会将观察结果与达勒姆开发的理论模型联系起来。