Relativistic reflection spectra of super-spinning black holes

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 $|a_{\ast }|>1$. 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-$\sigma$. We discuss our results and possible systematic uncertainties in the model.

12 pages, 8 figures. v2: refereed version