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arXiv · 1908.05177

Relativistic reflection spectra of super-spinning black holes

Biao Zhou·Ashutosh Tripathi·Askar B. Abdikamalov·Dimitry Ayzenberg·Cosimo Bambi·Sourabh Nampalliwar·Menglei Zhou
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Abstract

We construct a relativistic reflection model in a non-Kerr spacetime in which, depending on the value of the deformation parameter of the metric, there are black hole solutions with spin parameter $|a_*| > 1$. We apply our model to fit Suzaku data of four Seyfert galaxies (Ton S180, Ark 120, 1H0419-577, and Swift J0501.9-3239). These galaxies host at the center supermassive black holes that were previously interpreted as near-extremal Kerr black holes. For Ton S180 and 1H0419-577, our measurements are still consistent with the Kerr hypothesis. For Ark 120 and Swift J0501.9-3239, the Kerr solution is not recovered at 3-$σ$. We discuss our results and possible systematic uncertainties in the model.

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Biao Zhou, Ashutosh Tripathi, Askar B. Abdikamalov, Dimitry Ayzenberg, Cosimo Bambi, Sourabh Nampalliwar, Menglei Zhou. 2020-05-20. Relativistic reflection spectra of super-spinning black holes. https://doi.org/10.1140/epjc%2Fs10052-020-7998-3

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