Dynamics of charged-spinning particles around charged Kalb–Ramond black holes

Abstract

This work examines the dynamics of charged spinning test particles in the spacetime of a charged Kalb–Ramond (KR) black hole, characterized by its mass, electric charge, and a Lorentz symmetry-breaking parameter. The equations of motion for spinning, charged particles are derived using the Mathisson–Papapetrou–Dixon (MPD) equations, which incorporate both spin–curvature coupling and electromagnetic interactions. Using the spacetime’s symmetries, we obtain conserved quantities such as energy and angular momentum and employ them to construct the effective potential governing radial motion. The analysis focuses on circular trajectories and the properties of the innermost stable circular orbits (ISCOs), emphasizing how particle spin, black hole charge, and the Lorentz symmetry-breaking parameter modify orbital stability. Our results show that increases in spin and electric charge significantly alter the location of ISCOs. At the same time, the Lorentz symmetry-breaking parameter shifts the effective potential and changes the binding energy of orbits. Beyond orbital motion, we investigate high-energy processes by analyzing collisions of charged spinning particles near the event horizon. The conditions for reaching critical angular momentum are determined, and the resulting center-of-mass energy is computed. We demonstrate that the interplay between spin, electromagnetic interactions, and spacetime modifications can enhance collision energies, potentially producing signatures relevant for astrophysical observations. The study also addresses the emergence of superluminal motion in extreme regimes and identifies the bounds necessary for physically admissible trajectories. Overall, the results highlight how spin, charge, and KR corrections jointly shape particle dynamics, providing potential observational imprints of modified gravity in strong-field environments.