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arXiv · 2509.12318

Star-Black Hole Interactions in Young Star Clusters

Sara Rastello·Giuliano Iorio·Mark Gieles·Long Wang
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Abstract

Close encounters between stars and black holes can trigger micro-tidal disruption events (micro-TDEs) in dense young star clusters (YSCs). Using direct N-body simulations with PETAR, we found that most micro-TDEs arise from few-body multiple encounters. The inferred rate is approximately 350-450 Gpc$^{-3}$ yr$^{-1}$. Micro-TDEs could be detected both by upcoming surveys such as LSST, expected to observe roughly 10-100 events per year, and by their gravitational-wave (GW) signals peaking in the deci-Hertz band, detectable with future instruments such as LGWA and DECIGO.

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Sara Rastello, Giuliano Iorio, Mark Gieles, Long Wang. 2025-09-15. Star-Black Hole Interactions in Young Star Clusters. https://arxiv.org/abs/2509.12318

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