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arXiv · 2606.14833

Encounters of star clusters as a possible source of disturbances in their internal structure

M. D. Sizova·L. A. Maksimova·S. V. Vereshchagin
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Abstract

We searched for past close encounters of the Hyades and Pleiades with all 5736 clusters of the Hunt & Reffert catalog, integrating orbits with galpy over the last 100 Myr and validating candidates by Monte Carlo. Most nominally close pairs are unstable under catalog errors; only two remain reliable: Pleiades and HSC 751 and Hyades and HSC 2986. HSC 2986 coincides with the star-forming cloud Corona Australis, which the Hyades crossed about 5 Myr ago, passing ~11 pc from its dense core. Such interactions may be the cause of the mini-clusters discovered in the Pleiades.

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M. D. Sizova, L. A. Maksimova, S. V. Vereshchagin. 2026-06-12. Encounters of star clusters as a possible source of disturbances in their internal structure. https://arxiv.org/abs/2606.14833

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