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

TL;DR

This study uses Gaia DR3 data to analyze a rare septuple open cluster system and its extended family, revealing a nine-member association with common origins and coherent motions over millions of years.

Contribution

It identifies a new nine-member open cluster association using advanced clustering and statistical methods, providing insights into cluster multiplicity and Galactic structure.

Findings

Confirmed coherent motions over 20-30 million years

Identified a new candidate cluster in the system

Refined membership probabilities with multiple statistical models

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.