Particle dynamics and QPOs around a black hole coupled with nonlinear electrodynamics and cloud of strings

Abstract

We explore the motion of particles around a black hole coupled with nonlinear electrodynamics and a cloud of strings and examine the effects of the parameters of the black hole on the motion of particles. This black hole spacetime consists of five parameters, $M$ the mass of the black hole, $\alpha$ the deviation parameters that determine the deviation from the Bardeen black hole, $Q$ the magnetic charge, $\beta$ which describes the cloud of strings, and the parameter $K$ which describes the cosmological constant. We investigate the effect of these involved parameters on different physical quantities like horizon structure, effective potential, specific energy, angular momentum, innermost stable circular orbit and trajectories. Effective force is also discussed within the scope of different values of these involved parameters. We explore the oscillatory motion of neutral particles by perturbing the equations of motion near the stable circular orbits. Frequencies measured by local and distant observers are also calculated for the different choices of the involved parameters. Interestingly, Periastron precession is also investigated for the considered black hole solution. Lastly, we analyze the collision of two neutral test particles. All the investigated results are summarized with physically required behavior.