A code to compute the emission of thin accretion disks in non-Kerr space-times and test the nature of black hole candidates

TL;DR

This paper introduces a ray-tracing code to analyze electromagnetic emissions from thin accretion disks around black hole candidates, aiming to test whether these objects conform to the Kerr black hole model by examining deviations in space-time geometry.

Contribution

The paper presents a novel computational tool for modeling accretion disk emissions in non-Kerr space-times, enabling tests of black hole nature through X-ray data analysis.

Findings

Code can fit current X-ray data of black hole candidates.

Method constrains deviations from Kerr geometry.

Supports testing black hole hypotheses with observational data.

Abstract

Astrophysical black hole candidates are thought to be the Kerr black holes predicted by General Relativity, but the actual nature of these objects has still to be proven. The analysis of the electromagnetic radiation emitted by a geometrically thin and optically thick accretion disk around a black hole candidate can provide information about the geometry of the space-time around the compact object and it can thus test the Kerr black hole hypothesis. In this paper, I present a code based on a ray-tracing approach and capable of computing some basic properties of thin accretion disks in space-times with deviations from the Kerr background. The code can be used to fit current and future X-ray data of stellar-mass black hole candidates and constrain possible deviations from the Kerr geometry in the spin parameter-deformation parameter plane.