论文标题
Terzan 5是银河凸起的构件的残留物吗？ Apogee的证据
Is Terzan 5 the remnant of a building block of the Galactic bulge? Evidence from APOGEE
论文作者
论文摘要
已经提出，球状簇状的系统Terzan 5是银河系凸起的原始构建块的幸存残留物，这主要是由于年龄/金属性扩散及其恒星在$α$ -FE平面中的分布。我们采用来自Apache Point观测值银河进化实验（Apogee 2）的Sloan数字Sky调查（SDSS-IV）数据来检验这一假设。采用随机抽样技术，我们将Terzan 5星中10个元素的丰度与具有可比大气参数的凸出野外对应物的丰度进行了对比，发现它们在统计学上具有显着的水平上有所不同。两组之间的丰度在Ca，Mn，C，O和Al中的差异超过1 $σ$，在Si和Mg中的差异超过2 $σ$。 Terzan 5星的[$α$/fe]低于其凸起的恒星[Mn/fe]。鉴于这些差异，我们得出结论，Terzan 5不是凸起的$ $ $构件的残余。我们还根据星系的进化和组装及其环境（EAGLE）的宇宙数值模拟套件的预测来估算Terzan 5祖细胞的恒星质量，得出的结论可能已经低至$ \ sim3 \ sim3 \ times10^8 $ m $ m $ _ \ odot $，以至于它可能会出色地影响，以至于它可能会出现更大程度地影响。 （$ \ sim10^{10} $ m $ _ \ odot $）。我们简要讨论了Terzan 5性质的现有场景，并提出了一个观察性测试，以帮助阐明其起源。
It has been proposed that the globular cluster-like system Terzan 5 is the surviving remnant of a primordial building block of the Milky Way bulge, mainly due to the age/metallicity spread and the distribution of its stars in the $α$-Fe plane. We employ Sloan Digital Sky Survey (SDSS-IV) data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE 2) to test this hypothesis. Adopting a random sampling technique, we contrast the abundances of 10 elements in Terzan 5 stars with those of their bulge field counterparts with comparable atmospheric parameters, finding that they differ at statistically significant levels. Abundances between the two groups differ by more than 1$σ$ in Ca, Mn, C, O, and Al, and more than 2$σ$ in Si and Mg. Terzan 5 stars have lower [$α$/Fe] and higher [Mn/Fe] than their bulge counterparts. Given those differences, we conclude that Terzan 5 is not the remnant of a $major$ building block of the bulge. We also estimate the stellar mass of the Terzan 5 progenitor based on predictions by the Evolution and Assembly of GaLaxies and their Environments (EAGLE) suite of cosmological numerical simulations, concluding that it may have been as low as $\sim3\times10^8$ M$_\odot$ so that it was likely unable to significantly influence the mean chemistry of the bulge/inner disk, which is significantly more massive ($\sim10^{10}$ M$_\odot$). We briefly discuss existing scenarios for the nature of Terzan 5 and propose an observational test that may help elucidate its origin.
