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arXiv · 2205.15957

Analytic Modelling of Binary-Single Encounters: Non-Thermal Eccentricity Distribution and Gravitational-Wave Source Formation

Yonadav Barry Ginat·Hagai Perets
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Abstract

Chaotic three-body interactions may lead to the formation of gravitational-wave sources. Here, by modelling the encounter as a series of close, non-hierarchical, triple approaches, interspersed with hierarchical phases, in which the system consists of an inner binary and a star that orbits it, we compute the pericentre probability distribution, and thereby the in-spiral probability in any given binary-single encounter. We then consider the indirect influence of binary-single encounters on the population of gravitational-wave sources, by changing the eccentricity distribution of hard binaries in clusters; we calculate this distribution analytically, by requiring that it be invariant under interactions with single stars.

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Yonadav Barry Ginat, Hagai Perets. 2022-05-31. Analytic Modelling of Binary-Single Encounters: Non-Thermal Eccentricity Distribution and Gravitational-Wave Source Formation. https://doi.org/10.1093/mnrasl%2Fslac145

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