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arXiv · 2507.20165

Constraints on extra charges in dyonic Kerr-Newman-Kasuya-Taub-NUT black hole from the observations of quasi-periodic oscillations

Hamza Rehman·Saddam Hussain·Ghulam Abbas·Tao Zhu
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Abstract

This paper investigates the influence of the dimensionless electric charge ($Q/M$), magnetic charge ($P/M$), and Taub-NUT parameter ($n/M$) of a dyonic Kerr-Newman-Kasuya-Taub-NUT black hole on quasi-periodic oscillations (QPOs) observed in X-ray binaries. Using the relativistic precession model, we calculate the three fundamental frequencies arising from particle motion in the accretion disk around the black hole. These theoretical predictions are then confronted with observational QPO data from five X-ray binaries (GRO J1655-40, XTE J1859$+$226, XTE J1550-564, GRS 1915$+$105, and H1743-322), and the Markov Chain Monte Carlo technique is used to constrain the black hole parameters. Our analysis reveals no significant evidence for nonzero values of $Q/M$ and $P/M$ across all sources, thereby allowing us to place several stringent upper limits on electric charge ($Q/M$) and magnetic charge ($P/M$) of the black hole in these systems. Similarly, no compelling indication of a nonzero Taub-NUT parameter is found in QPOs from GRO J1655-40, XTE J1859$+$226, XTE J1550-564, and H1743-322. In contrast, the posterior distribution derived from GRS 1915$+$105 data suggests a nonzero Taub-NUT parameter, i.e., gravitomagnetic monopole moment. This result indicates a potential deviation from the Kerr metric in this astrophysical black hole.

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Hamza Rehman, Saddam Hussain, Ghulam Abbas, Tao Zhu. 2025-07-27. Constraints on extra charges in dyonic Kerr-Newman-Kasuya-Taub-NUT black hole from the observations of quasi-periodic oscillations. https://arxiv.org/abs/2507.20165

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