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arXiv · 2412.04249

Approach to the separatrix with eccentric orbits

Guillaume Lhost·Geoffrey Compère
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Abstract

Eccentric binary compact mergers are prime targets of current and future gravitational wave observatories. In the small mass ratio expansion, post-adiabatic inspirals have been modeled up to the separatrix, where first-principle modeling currently ends. In this paper, we derive the analytic late time solution to the adiabatic inspiral in terms of self-force coefficients at the separatrix. We identify the role of the Lambert $W_{-1}$ function as a key mathematical ingredient in the approach to the separatrix.

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Guillaume Lhost, Geoffrey Compère. 2024-12-05. Approach to the separatrix with eccentric orbits. https://doi.org/10.21468/scipostphyscore.8.3.059

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