Evolution and Dynamics of the Milky Way using the Gaia satellite mission

随着盖亚卫星使命的出现，我们终于可以非常详细地研究银河系广泛区域内恒星的位置、运动、年龄和金属丰度。盖亚的第一批数据已经揭示了一个不可预见的丰富的子结构，从银河系圆盘中的垂直波和相位螺旋到恒星运动与银河棒共振产生的巨大平面运动模式（也可能是螺旋模式）。我们的团队已经使用这些共振模式首次证明/测量了银河棒的慢化，并提供了暗物质的惯性质量吸收棒角动量的第一个证据。（从而为缺乏这种质量的修正重力模型提供了强大的张力）。在这个博士项目中，我们都将看到来自盖亚的进一步数据发布，这将扩大这一分析所探测的范围，无论是从盖亚RV子集还是结合后续调查，都可以获得具有附加年龄和恒星丰度的主要数据集-后者编码了恒星的诞生地点和时间，从而使我们能够重建系统的动态历史。在这些一般参数内，Kit（Christopher）将根据自己的喜好自由发展。该项目涉及分析可用数据，提高其质量，将分析模型与数据进行比较，和/或创建理论模拟，以捕获星系的演化并识别区分不同过程的可观测值，例如暗物质晕的不同参数化。虽然基特可以随时选择转移焦点，但我从我们目前的谈话中得知，他的兴趣集中在理论部分。在这方面的研究中，我们的小组（与海德堡和莱斯特合作）开发了一种定制的N体模拟策略，使我们能够运行具有真实结构（连续星星形成）的高效低成本星系模拟，同时控制例如星星形成历史，轮廓，合并等。Kit将使用改进的分析模型解释这些模拟，然后与数据进行比较。通过这个项目，他将为理解：圆盘加热，圆盘中的径向迁移，共振行为和子结构做出贡献，并解决暗物质的分布和性质。在项目期间，我们将确保Kit发展：在更广泛的领域对天文学的坚定理解，对银河系动力学的坚定理解。此外，基特将提高他的编程技能（基于C++和Python），将提高他在大规模并行计算，主要科学作品的写作，演讲技巧，以及在更大的合作范围内组织/指导自己的研究方面的技能。

With the advent of the Gaia satellite mission, we can finally study the positions, motions, ages, and metallicities of stars across a wide sector of the Milky Way galaxy in great detail. The first data releases of Gaia have already revealed an unforeseen wealth of substructure, ranging from the vertical waves and phase spiral in the Galactic disc to the vast patterns of in-plane motions created by resonances of stellar motions with the galactic bar (and potentially also spiral pattern). Our group has already used these resonant patterns to prove/measure for the first time the slow-down of the Galactic bar and to provide the first evidence for the inertial mass of dark matter absorbing the angular momentum of the bar (thus providing strong tension with modified gravity models that lack this mass).During this PhD project, we will both see further data releases from Gaia, which will extend the range probed by this analysis, and both from the Gaia RV subset and combination with follow-up surveys obtain major datasets with added ages and stellar abundances - the latter encode the birth place and time of stars and thus allow us to reconstruct the dynamic history of the system. Within these general parameters, Kit (Christopher) will be given freedom to develop according to his own preferences. The project involves analysing the available data, improving their quality, comparing analytical models to the data, and/or creating theoretical simulations that capture the evolution of the galaxy and identify observables that discriminate between different processes, and e.g. different parametrisations for the dark matter halo. While Kit will be given the choice at any time to shift the focus, I take from our current conversation that his interests are concentrated on the theoretical parts. In this line of research, our group has (in collaboration with Heidelberg and Leicester) developed a strategy of tailored N-body simulations that allow us to run efficient low/cost galaxy simulations with realistic structure (continuous star formation) while controlling e.g. star formation histories, profiles, mergers, etc.. Kit will interpret these simulations with improved analytical models and then compare to the data. With this, he will contribute to understanding: disc heating, radial migration in disc, resonant behaviour and substructure, and address the distribution and properties of dark matter.During the project we will ensure that Kit develops: a firm understanding of astronomy also in a wider area, a firm understanding of Galactic dynamics. Further, Kit will improve his skills in programming (based on C++ and python), will improve his skills in large-scale parallelised computing, the writing of major scientific works, presentation skills, and organising/directing his own research within the context of a larger collaboration.