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arXiv · 2303.10380

Blind Search of The Solar Neighborhood Galactic Disk within 5kpc: 1,179 new Star clusters found in Gaia DR3

Huanbin Chi·Feng Wang·Wenting Wang·Hui Deng·Zhongmu Li
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Abstract

Studying open clusters (OCs) is essential for a comprehensive understanding of the structure and evolution of the Milky Way. Many previous studies have systematically searched for OCs near the solar system within 1.2 kpc or 20 degrees of galactic latitude. However, few studies searched for OCs at higher galactic latitudes and deeper distances. In this study, based on a hybrid unsupervised clustering algorithm (Friends-of-Friends and pyUPMASK) and a binary classification algorithm (Random Forest), we extended the search region (i.e., galactic latitude |b|>=20 degrees) and performed a fine-grained blind search of Galactic clusters in Gaia DR3. After cross-matching, the newly discovered cluster candidates are fitted using isochrone fitting to estimate the main physical parameters (age and metallicity) of these clusters. These cluster candidates were then checked using manual visual inspection. Their statistical properties were compared with previously exposed cluster catalogs as well. In the end, we found 1,179 new clusters with considerable confidence within 5kpc.

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Huanbin Chi, Feng Wang, Wenting Wang, Hui Deng, Zhongmu Li. 2023-03-18. Blind Search of The Solar Neighborhood Galactic Disk within 5kpc: 1,179 new Star clusters found in Gaia DR3. https://doi.org/10.3847/1538-4365/accb50

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