# Relativistic reflection spectra of super-spinning black holes

## TL;DR

This paper develops a relativistic reflection model for super-spinning black holes in non-Kerr spacetimes and applies it to Seyfert galaxy data, challenging the Kerr black hole interpretation in some cases.

## Contribution

It introduces a new reflection model for non-Kerr black holes with spin > 1 and tests it against observational data, providing alternative explanations for supermassive black hole spins.

## Key findings

- Some galaxies' data are consistent with Kerr black holes.
- Others suggest deviations from Kerr at 3-sigma confidence.
- The model highlights potential systematic uncertainties.

## 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-$\sigma$. We discuss our results and possible systematic uncertainties in the model.