Shadows, greybody factors, emission rate, topological charge, and phase transitions for a charged black hole with a Kalb-Ramond field background

TL;DR

This paper studies a charged black hole with a Kalb-Ramond field, analyzing its shadow, greybody factors, topological charge, and phase transitions, and compares results with observational data from the EHT.

Contribution

It introduces a comprehensive analysis of a Kalb-Ramond charged black hole, including shadow, emission, topological charge, and phase transition properties, with observational constraints.

Findings

Calculated photon sphere and shadow radii consistent with EHT data

Analyzed greybody factors and emission rates for the black hole

Identified phase transitions through heat capacity analysis

Abstract

In this work, we investigate a spherically symmetric charged black hole in the presence of a Kalb--Ramond field background. We calculate the photon sphere and shadow radii and, corroborating our results, we constrain them from observational data from the Event Horizon Telescope (EHT), particularly focusing on the shadow images of Sagittarius $A^{*}$. Additionally, we analyze the greybody factors, emission rate, and partial absorption cross section. We also examine the topological charge and its application to the deflection angle. Finally, we conduct the analysis of the heat capacity and phase transitions.