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arXiv · 2601.03415

Superradiant scattering by rotating black-bounce black holes

Pedro Henrique Croti Siqueira·Maurício Richartz
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Abstract

We investigate superradiant scattering off a rotating regular black hole described by a black-bounce metric which generalizes the Kerr spacetime of mass $M$ and specific angular momentum $a$ through a regularization parameter $p$ and two deformation exponents $(k,n)$. Focusing on massless $(\ell,m)=(1,1)$ scalar modes, we explore the parameter space and compute amplification factors by numerically integrating the separated radial Klein-Gordon equation. We track the peak amplification and the corresponding frequency across the $(a/M,p/M)$ parameter space for several combinations of $k$ and $n$. We find that increasing $n$ systematically enhances superradiance, whereas increasing $k$ tends to suppress it. In particular, certain configurations yield amplification levels up to 98% larger than the maximum amplification for standard Kerr black holes.

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Pedro Henrique Croti Siqueira, Maurício Richartz. 2026-01-06. Superradiant scattering by rotating black-bounce black holes. https://arxiv.org/abs/2601.03415

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