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arXiv · 2111.04900

Dynamics of charged particles moving around Kerr black hole with inductive charge and external magnetic field

Xin Sun·Xin Wu·Yu Wang·Chen Deng·Baorong Liu·Enwei Liang
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Abstract

We mainly focus on the effects of small changes of parameters on the dynamics of charged particles around the Kerr black hole surrounded by an external magnetic field, which can be considered as a tidal environment. The radial motions of charged particles on the equatorial plane are studied via an effective potential. It is found that the particle energies at the local maxima values of the effective potentials increase with an increase of the black hole spin and the particle angular momenta, but decrease with an increase of one of the inductive charge parameter and magnetic field parameter. The radii of stable circular orbits on the equatorial plane also increase, whereas those of the innermost stable circular orbits decrease. On the other hand, the effects of small variations of the parameters on the orbital regular and chaotic dynamics of charged particles on the non-equatorial plane are traced by means of a time-transformed explicit symplectic integrator, Poincar\'{e} sections and fast Lyapunov indicators. It is shown that the dynamics sensitively depends on small variations of the inductive charge parameter, magnetic field parameter, energy and angular momentum. Chaos occurs easily as each of the dynamical parameters increases. When the dragging effects of the spacetime increase, the chaotic properties are not always weakened under some circumstances.

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Xin Sun, Xin Wu, Yu Wang, Chen Deng, Baorong Liu, Enwei Liang. 2021-11-09. Dynamics of charged particles moving around Kerr black hole with inductive charge and external magnetic field. https://doi.org/10.3390/universe7110410

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