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arXiv · 2302.02750

A detection of the layered structure of nearby open clusters

Qingshun Hu·Yu Zhang·Ali Esamdin·Hong Wang·Mingfeng Qin
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Abstract

We applied the newly developed rose diagram overlay method to detect the layered structure of 88 nearby open clusters ($\leq$500~pc) on the three projections after the distance correction of their member stars, based on the catalog in literature. The results show that with the rose diagram overlay method, a total of 74 clusters in our sample have a layered structure, while the remaining clusters are without a clear layered structure. We for the first time defined the layered structure parameters for the sample clusters. Meanwhile, we found that the layered circle core area ($s$) has a strong positive correlation with the number of cluster members, while the kernel instability index ($\eta$) has a strong negative correlation with the number of cluster members. Our study provides a novel perspective for the detection of the layered structure of open clusters.

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Qingshun Hu, Yu Zhang, Ali Esamdin, Hong Wang, Mingfeng Qin. 2023-02-06. A detection of the layered structure of nearby open clusters. https://doi.org/10.1051/0004-6361%2F202244199

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