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arXiv · 2501.17235

A Detailed Analysis of Close Binary OCs

Seval Taşdemir·Deniz Cennet Çınar
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Abstract

In this study, we analyzed the close binary open clusters CWNU 2666 and HSC 224, which are in close spatial proximity, using photometric and astrometric data from the {\it Gaia} DR3 catalog. Likely member stars were identified based on a membership probability threshold ($P \geq 0.5$), resulting in 106 and 146 members for CWNU 2666 and HSC 224, respectively. The mean proper motion components ($\mu_{\alpha}\cos\delta$, $\mu_{\delta}$) were determined to be (0.646$\pm$0.155, -0.769$\pm$0.124) mas yr$^{-1}$ for CWNU 2666, and (0.665$\pm$0.131, -0.728$\pm$0.107) mas yr$^{-1}$ for HSC 224. The isochrone distances ($d_{\rm iso}$) were estimated as 1885$\pm$44 pc for CWNU 2666 and 1866$\pm$29 pc for HSC 224. The corresponding cluster ages ($t$) were derived as 160$\pm$15 Myr and 140$\pm$15 Myr, respectively. The astrometric and fundamental astrophysical parameters derived in this study demonstrate that the two open clusters are a close pair of open clusters.

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Seval Taşdemir, Deniz Cennet Çınar. 2025-01-28. A Detailed Analysis of Close Binary OCs. https://arxiv.org/abs/2501.17235

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