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arXiv · 2507.11859

Extracting energy from plunging region of a Kerr-Taub-NUT black hole by magnetic reconnection

Zhengwei Cheng·Songbai Chen·Jiliang Jing
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Abstract

We have studied the energy extraction from a Kerr-Taub-NUT black hole via magnetic reconnection occurring in the plunging region. Our results show that the gravitomagnetic charge suppresses the energy extraction process through magnetic reconnection and reduces the corresponding extraction efficiency, which is opposite to the effects of the black hole spin and the magnetization parameter. Finally, we treat the energy extraction process through magnetic reconnection as a mechanism to revisit the problem of the observed jet power and radiative efficiency of GRS 1915+105. Our results show that the allowed black hole parameter region originating from the jet power has an intersection with the region from the radiative efficiency. This means that with this mechanism related to magnetic reconnection the Kerr-Taub-NUT metric can simultaneously explain the observed jet power and radiative efficiency for GRS 1915+105, which is not explained by other mechanisms in previous studies.

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Zhengwei Cheng, Songbai Chen, Jiliang Jing. 2025-07-16. Extracting energy from plunging region of a Kerr-Taub-NUT black hole by magnetic reconnection. https://arxiv.org/abs/2507.11859

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