# Probing the Black Hole Engine with Measurements of the Relativistic X-ray Reflection Component

## TL;DR

This paper reviews the use of X-ray spectroscopy to measure black hole parameters, especially the relativistic reflection component, highlighting future observational and theoretical challenges in black hole studies.

## Contribution

It discusses the upcoming challenges and prospects in measuring black hole properties through X-ray reflection spectroscopy in the next decade.

## Key findings

- X-ray spectroscopy effectively estimates black hole spin and parameters.
- Relativistic reflection component is key to understanding black hole accretion.
- Future challenges include observational limitations and theoretical modeling complexities.

## Abstract

Over the last decades X-ray spectroscopy has proven to be a powerful tool for the estimation of black hole spin and several other key parameters in dozens of AGN and black hole X-ray binaries. In this White Paper, we discuss the observational and theoretical challenges expected in the exploration, discovery, and study of astrophysical black holes in the next decade. We focus on the case of accreting black holes and their electromagnetic signatures, with particular emphasis on the measurement of the relativistic reflection component in their X-ray spectra.