The Physical Properties of the Accreted Satellites of the Milky Way.

这个项目的目的是研究银河系中吸积的矮星系的性质，这些星系如今构成了银河系晕恒星质量预算的相当大一部分质量。人们感兴趣的主要性质是矮小星系的质量、重子历史(即恒星形成和化学富集史)和吸积时间。Mackereth等人(2019)在星系及其环境的演化和组装(EAGLE)模拟中研究了类银河系吸积卫星的这些特性，并提出这些卫星的质量与它们在阿尔法铁平面上的恒星丰度模式密切相关。我们将进一步探索化学对质量和其他参数的依赖，如与中心晕的相互作用史、粒子结合能和吸积时间，目的是探索EAGLE中化学性质和重子历史之间的理论联系。在该项目的下一阶段，将利用从研究EAGLE模拟中获得的知识来描述构成银河晕的被吸积卫星的特性，并将其应用于远地点和编织测量的数据。将根据内部开发的分析技术选择感兴趣的样本，以便在对调查选择效果进行校正后确定银河系组件的轨道性质和结构参数。最终，比较~10^6光晕恒星的化学动力学性质和EAGLE预测，将使我们能够完整地描述组成银河系光晕的恒星群体的性质。

The aim of this project is to investigate the properties of dwarf galaxies that were accreted onto the Milky Way and today make up a substantial mass fraction of the stellar mass budget of its halo. The main properties of interest are mass, baryonic history (i.e., star formation and chemical enrichment histories) and accretion time of dwarf galaxies. Mackereth et al (2019) studied these properties of accreted satellites of Milky Way-like galaxies in the Evolution and Assembly of GaLaxies and their Environments (EAGLE) simulations and suggested that the masses of these satellites are strongly correlated with their stellar abundance patterns in the alpha-iron plane. We will further explore the dependence of chemistry on mass and other parameters, such as the history of interaction with the central halo, particle binding energy and accretion time with the goal of probing theoretical connections between chemical properties and baryon histories in EAGLE. In the next stage of the project the knowledge acquired from studying the EAGLE simulations will be employed in order to characterise the properties of accreted satellites that make up the Milky Way halo and applied to data from the APOGEE and WEAVE surveys. The sample of interest will be selected on the basis of analysis techniques developed in-house to determine the orbital properties and structural parameters of galactic components after correction for survey selection effects. Ultimately, comparison between the chemodynamic properties of ~10^6 Halo stars and EAGLE predictions will enable a complete characterisation of the properties of the stellar populations that comprise the Milky Way's halo.