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arXiv · 2301.05317

Next-to-leading-order solution to Kerr-Newman black hole superradiance

Shou-Shan Bao·Qi-Xuan Xu·Hong Zhang
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Abstract

The superradiant instabilities of Kerr-Newman black holes with charged or uncharged massive spin-0 fields are calculated analytically to the next-to-leading order in the limit of $\alpha\sim r_g \mu \ll 1$. A missing factor of $1/2$ in the previous leading-order result is identified. The next-to-leading order result has a compact form and is in good agreement with existing numerical calculations. The percentage error increases with $\alpha$, from a few percent for $\alpha\sim 0.1$ to about $50\%$ for $\alpha\sim 0.4$. Massive neutral scalars too heavy to be produced with Kerr black hole superradiance may exist in the superradiant region of Kerr-Newman black holes.

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Shou-Shan Bao, Qi-Xuan Xu, Hong Zhang. 2023-01-12. Next-to-leading-order solution to Kerr-Newman black hole superradiance. https://doi.org/10.1103/physrevd.107.064037

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