# Modelling the polarised emission from black holes on event horizon-scales

## TL;DR

This paper introduces a new polarised general-relativistic radiative transfer code, BHOSS, enabling realistic imaging of black holes on event horizon-scales and aiding the understanding of their surrounding accretion flows.

## Contribution

The paper presents BHOSS, a novel code that accurately models polarised radiative transfer in strong gravity, improving the realism of black hole imaging and analysis.

## Key findings

- Provides physically-realistic black hole images
- Enhances understanding of accretion flow properties
- Supports interpretation of horizon-scale observations

## Abstract

Upcoming VLBI observations will resolve nearby supermassive black holes, most notably Sagittarius A* and M87, on event horizon-scales. Recent observations of Sagittarius A* with the Event Horizon Telescope have revealed horizon-scale structure. Accordingly, the detection and measurement of the back hole ``shadow" is expected to enable the existence of astrophysical black holes to be verified directly. Although the theoretical description of the shadow is straightforward, its observational appearance is largely determined by the properties of the surrounding accretion flow, which is highly turbulent. We introduce a new polarised general-relativistic radiative transfer code, \texttt{BHOSS}, which accurately solves the equations of polarised radiative transfer in arbitrary strong-gravity environments, providing physically-realistic images of astrophysical black holes on event horizon-scales, as well as also providing insight into the fundamental properties and nature of the surrounding accretion flow environment.