论文标题
关于银河系中旋转金属贫困恒星种群的起源
On the origin of a rotating metal-poor stellar population in the Milky Way Nuclear Cluster
论文作者
论文摘要
我们探讨了最近在银河系核簇（NC）内检测到的恒星群的起源，该恒星具有与主导群体相比表现出亚光金属性和更高旋转的恒星。使用最先进的$ n $体体模拟，我们将巨大的恒星系统的插座建模到银河系中心，包括银河系和半乳酸外部。我们表明，新发现的人口可以是距银河中心（银河场景）几个KPC形成的巨大恒星集群的残余物，或者是从10-100 kpc的矮人星系中吸收的，最初位于10-100 kpc（最初的层状场景），并到达了3-5 Gyr的Galactic Center 3-5 Gyr。我们的模型与银河系卫星和球形簇的特征性半乳酸距离和金属性分布之间的比较有利于银河系。与与Esceladus-Sausage，Sequoia，Sagittarius和Canis主要结构相关的簇的比较表明，观察到的金属贫困亚结构的祖细胞是在阳性内形成的，而不是被吸收。
We explore the origin of a population of stars recently detected in the inner parsec of the Milky Way Nuclear Cluster (NC), which exhibit sub-solar metallicity and a higher rotation compared to the dominant population. Using state-of-the-art $N$-body simulations, we model the infall of a massive stellar system into the Galactic center, both of Galactic and extra-galactic origin. We show that the newly discovered population can either be the remnant of a massive star cluster formed a few kpc away from the Galactic center (Galactic scenario) or be accreted from a dwarf galaxy originally located at 10-100 kpc (extragalactic scenario) and that reached the Galactic center 3-5 Gyr ago. A comparison between our models and characteristic Galactocentric distance and metallicity distributions of Milky Way satellites and globular clusters favours the Galactic scenario. A comparison with clusters associated with the Enceladus-Sausage, Sequoia, Sagittarius and Canis Major structures suggests that the progenitor of the observed metal-poor substructure formed in-situ rather than being accreted.
