Repetitive Penrose Process in Kerr-Taub-NUT black hole spacetime

TL;DR

This paper investigates the repetitive Penrose process in Kerr-Taub-NUT black holes, analyzing how gravitomagnetic charge affects horizon structure, energy extraction, and iterative energy transfer efficiency.

Contribution

It introduces a detailed analysis of the repetitive Penrose process in Kerr-Taub-NUT black holes, highlighting the impact of gravitomagnetic charge on energy extraction.

Findings

Event horizon and ergosphere radii increase with gravitomagnetic charge

Extractable energy decreases as gravitomagnetic charge rises

Numerical analysis of iterative energy transfer in the process

Abstract

In this article, we study the repetitive Penrose process for the Kerr-Taub-NUT black hole (BH). First of all, we briefly review the spacetime of the Kerr-Taub-NUT BH, including horizon and ergosphere structures. The results indicate that the event horizon and ergosphere radii increase under the influence of the gravitomagnetic charge $l$. Subsequently, we find by using the irreducible mass of the BH that the extractable energy decreases with the rise of the gravitomagnetic charge. We then turn to the repetitive Penrose process by writing the conservation laws and setting the corresponding iterative stopping conditions. Furthermore, we numerically calculate the change in the BH's parameters, along with the corresponding quantities of the repetitive Penrose process, for each iteration.