Self-consistent modelling of star cluster evolution: Initial conditions and the origin of the stellar population II halo of the Milky Way

直到最近，人们才意识到球状星团（GC）演化的最早阶段的信息，即GC中恒星形成的残余气体的去除，可能仍然包含在今天的观测数据中。这提供了一种方法，使用自洽体计算来回溯GC到它们可能的初始状态。此外，有人提出，银河系的恒星族II晕起源于溶解的星星团和银河系晕星的比例，已形成的星星团可以量化。由于我们银河系中最古老的GC见证了银河系的形成，并且GC的气体排出受到银河系潮汐场的影响，因此GC出生时暴露的条件允许重建银河系的形成历史。因此，我们的目标是首次进行高精度的研究，以研究星星团的自洽演化，包括残余气体排出，变化的潮汐场环境和经典的两体弛豫驱动的演化。结果将解开由这些物理过程驱动的影响，并将研究给定观测数据的允许初始条件的范围。这将提供对早期星星团形成过程的深入了解，并将限制银河系形成的详细事件。

Only recently it became appreciated that information from the earliest phase of globular cluster (GC) evolution, the removal of the residual-gas from which the stars of a GC formed, may still be contained in present-day observational data. This provides a means to back-trace GCs to their probable initial states using self-consistent \Nbody computations. It has furthermore been suggested that the stellar population II halo of the Milky originates from dissolving star clusters and the fraction of Galactic halo stars that have formed in star clusters may be quantified. Since the oldest GCs in our Galaxy have witnessed the formation of the Milky Way (MW) and since gas-expulsion from GCs is influenced by the evolving tidal-field of the MW, the conditions GCs were exposed to at birth allow a reconstruction of the MW's formation history.We therefore aim to perform for the first-time a high-precision \Nbody study to investigate star cluster evolution self-consistently, including residual-gas expulsion, a changing tidal-field environment and classical two-body relaxation driven evolution. The results will disentangle effects driven by these physical processes and the range of allowed initial conditions, given the observational data, will be investigated. This will provide insights into the early star cluster formation processes and will constrain the detailed events of the formation of the Galaxy.