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arXiv · 2107.06085

Circular motion around a regular rotating Hayward black hole

Saeed Ullah Khan·Jingli Ren·Javlon Rayimbaev
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Abstract

In this article, we explore the geodesics motion of neutral test particles and the process of energy extraction from a regular rotating Hayward black hole. We analyse the effect of spin, as well as deviation parameter $g$, on ergoregion, event horizon and static limit of the said black hole. By making use of geodesic equations on the equatorial plane, we determine the innermost stable circular and photon orbits. Moreover, we investigate the effective potentials and effective force to have information on motion and the stability of circular orbits. On studying the negative energy states, we figure out the energy limits of Penrose mechanism. Using Penrose mechanism, we found expression for the efficiency of energy extraction and observed that both spin and deviation parameters, contribute to the efficiency of energy extraction. Finally, the obtained results are compared with that acquired from Kerr and braneworld Kerr black holes.

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Saeed Ullah Khan, Jingli Ren, Javlon Rayimbaev. 2021-07-08. Circular motion around a regular rotating Hayward black hole. https://doi.org/10.1142/s021773232250064x

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