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arXiv · 2310.18686

Ringdown gravitational waves from close scattering of two black holes

Yeong-Bok Bae·Young-Hwan Hyun·Gungwon Kang
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Abstract

We have numerically investigated close scattering processes of two black holes (BHs). Our careful analysis shows for the first time a non-merging ringdown gravitational wave coming from dynamical tidal deformations of individual BHs during their close encounter. The ringdown wave frequencies turn out to agree well with the quasi-normal ones of a single BH in perturbation theory, despite its distinctive physical context from the merging case. Our study shows a new type of gravitational waveform and opens up a new exploration of strong gravitational interactions using BH encounters.

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Yeong-Bok Bae, Young-Hwan Hyun, Gungwon Kang. 2023-10-28. Ringdown gravitational waves from close scattering of two black holes. https://arxiv.org/abs/2310.18686

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