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arXiv · 2307.08697

Towards numerical-relativity informed effective-one-body waveforms for dynamical capture black hole binaries

Tomas Andrade·Juan Trenado·Simone Albanesi·Rossella Gamba·Sebastiano Bernuzzi·Alessandro Nagar·Juan Calderon-Bustillo·Nicolas Sanchis-Gual·Jose A. Font·William Cook·Boris Daszuta·Francesco Zappa·David Radice
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Abstract

Dynamical captures of black holes may take place in dense stellar media due to the emission of gravitational radiation during a close passage. Detection of such events requires detailed modelling, since their phenomenology qualitatively differs from that of quasi-circular binaries. Very few models can deliver such waveforms, and none includes information from Numerical Relativity (NR) simulations of non quasi-circular coalescences. In this study we present a first step towards a fully NR-informed Effective One Body (EOB) model of dynamical captures. We perform 14 new simulations of single and double encounter mergers, and use this data to inform the merger-ringdown model of the TEOBResumS-Dali approximant. We keep the initial energy approximately fixed to the binary mass, and vary the mass-rescaled, dimensionless angular momentum in the range $(0.6, 1.1)$, the mass ratio in $(1, 2.15)$ and aligned dimensionless spins in $(-0.5, 0.5)$. We find that the model is able to match NR to $97%$, improving previous performances, without the need of modifying the base-line template. Upon NR informing the model, this improves to $99%$ with the exception of one outlier corresponding to a direct plunge. The maximum EOBNR phase difference at merger for the uninformed model is of $0.15$ radians, which is reduced to $0.1$ radians after the NR information is introduced. We outline the steps towards a fully informed EOB model of dynamical captures, and discuss future improvements.

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Tomas Andrade, Juan Trenado, Simone Albanesi, Rossella Gamba, Sebastiano Bernuzzi, Alessandro Nagar, Juan Calderon-Bustillo, Nicolas Sanchis-Gual, Jose A. Font, William Cook, Boris Daszuta, Francesco Zappa, David Radice. 2023-07-17. Towards numerical-relativity informed effective-one-body waveforms for dynamical capture black hole binaries. https://arxiv.org/abs/2307.08697

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