Hierarchical formation of Westerlund 1

We examine the level of substructure and mass segregation in the massive, young cluster Westerlund 1. We find that it is relatively smooth, with little or no mass segregation,...本研究针对大质量年轻星团韦斯特伦德1号（Westerlund 1）的子结构（substructure）与质量分异（mass segregation）程度展开分析。我们发现该星团结构相对均匀，几乎不存在或仅存在极微弱的质量分异现象……