论文标题
欧米茄半人马座中的子人群的正确运动
The proper motion of sub-populations in Omega Centauri
论文作者
论文摘要
银河球簇欧米茄半人马座是同类中最大的，具有多个恒星种群和几种运动学和动力学特征的复杂混合物。在三个主要的子人群中发现了不同的适当运动，这意味着最丰富的金属含量是积聚的。这一特殊的证据一直是辩论问题，因为可用的数据要么不够精确，要么限于集群的一小部分，以最终确认或反驳结果。使用第二GAIA数据释放和最近高质量的多波段光度法的天文学，我们现在可以解决争议。我们使用GAIA数据重现了原始分析，发现这三个群体具有相同的平均正确运动。因此，无需为最富含金属的亚种群援引积聚的起源。
The galactic globular cluster Omega Centauri is the most massive of its kind, with a complex mix of multiple stellar populations and several kinematic and dynamical peculiarities. Different mean proper motions have been detected among the three main sub-populations, implying that the most metal-rich one is of accreted origin. This particular piece of evidence has been a matter of debate because the available data have either not been sufficiently precise or limited to a small region of the cluster to ultimately confirm or refute the result. Using astrometry from the second Gaia data release and recent high-quality, multi-band photometry, we are now in a position to resolve the controversy. We reproduced the original analysis using the Gaia data and found that the three populations have the same mean proper motion. Thus, there is no need to invoke an accreted origin for the most metal-rich sub-population.
