论文标题
在年轻的大型麦哲伦云集群NGC NGC 2173中，将分叉的红色巨型分支解码为多个恒星种群的示踪剂
Decoding the bifurcated red-giant branch as a tracer of multiple stellar populations in the young Large Magellanic Cloud cluster NGC 2173
论文作者
论文摘要
在几乎所有古老的银河球状簇中，代表星际光元素丰度变化的多个恒星种群（MP）很常见。在这里，我们提供的最有力的证据表明，人口大约1.7 Gyr gyr的大型麦哲伦云簇NGC 2173也表现出光元素丰度的变化。因此，我们的结果表明NGC 2173是迄今已确认MP的最年轻的集群。我们的结论是基于其红色巨型分支的尖端上的独特分叉，在高质量的色彩图中，是由哈勃空间望远镜成像观测值产生的。对“伪$ ubi $”地图的详细分析，我们的结果进一步支持了，该分析揭示了该集群红色巨型分支颜色分布中双峰性的明确证据。麦哲伦云中的年轻簇可以为银河发展历史提供关键的见解。我们在NGC 2173中对MPS的发现表明，古老的银河球状簇和年轻的大型群集可能会共享一个共同的地层过程。
Multiple stellar populations (MPs) representing star-to-star light-element abundance variations are common in nearly all ancient Galactic globular clusters. Here we provide the strongest evidence yet that the populous, ~ 1.7 Gyr-old Large Magellanic Cloud cluster NGC 2173 also exhibits light-element abundance variations. Thus, our results suggest that NGC 2173 is the youngest cluster for which MPs have been confirmed to date. Our conclusion is based on the distinct bifurcation at the tip of its red-giant branch in high-quality color--magnitude diagrams generated from Hubble Space Telescope imaging observations. Our results are further supported by a detailed analysis of 'pseudo-$UBI$' maps, which reveal clear evidence of a bimodality in the cluster's red-giant-branch color distribution. Young clusters in the Magellanic Clouds can provide critical insights into galaxy evolution histories. Our discovery of MPs in NGC 2173 suggests that ancient Galactic globular clusters and young massive clusters might share a common formation process.
