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arXiv · 2604.23093

Analysis of a Septuple Open Cluster System and Its Extended Family in Gaia DR3

Muhammad Akmal Husain·Ferdinand·Mochamad Ikbal Arifyanto·Muhammad Irfan Hakim
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Abstract

A rare multiple open cluster system has been analyzed using Gaia DR3 astrometry and photometry data. Using Agglomerative Hierarchical clustering and Bayesian-HDBSCAN, we identify a compact core consisting of seven known open clusters and two additional components, including a new candidate, forming a nine-member association. Membership probabilities are refined through statistical modeling, combining GUMM, Bayesian-KDE, and Bayesian-XDGMM for tidal tails identification. Backward orbital integrations confirm coherent motions over 20-30 million years, suggesting a common origin from the same massive molecular cloud. This system offers a unique laboratory for investigating cluster multiplicity, dynamical evolution, and Galactic structure.

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Muhammad Akmal Husain, Ferdinand, Mochamad Ikbal Arifyanto, Muhammad Irfan Hakim. 2026-04-25. Analysis of a Septuple Open Cluster System and Its Extended Family in Gaia DR3. https://arxiv.org/abs/2604.23093

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