Magnetized Letelier black hole in AdS spacetime

Abstract

In this study, we investigate the motion of charged, neutral, and light-like particles in a magnetized black hole solution surrounded by a cloud of strings in an anti-de Sitter (AdS) background. This spacetime admits several well-known solutions as special cases, including the Letelier-AdS black hole, the Melvin spacetime, and the Schwarzschild-AdS black hole. We demonstrate that key parameters characterizing the geometry-such as the cloud of strings parameter, the magnetic field strength, and the AdS radius-significantly affect the trajectories of these particles. Our analysis shows that increasing the cloud of strings parameter weakens the gravitational influence, while the magnetic field introduces additional attractive components that can destabilize particle orbits. We examine the photon sphere and calculate the black hole shadow, showing that the shadow radius decreases with increasing magnetic field parameter but increases with the cloud of strings parameter. These findings provide potential observables for distinguishing between different black hole models in realistic astrophysical environments.

Figures (19)

• Figure 1: Plot shows the configuration of magnetic field lines in the environment of the magnetized Letelier BH in AdS spacetime for various combinations of magnetic field parameter $B=0.05,\,0.1,\,0.5$ while keeping $\alpha=0.3$ and $\ell_p=10$ fixed, corresponding to panels from left to right. Note that the gray-shaded area refers to the BH horizon. Note that the magnetic field parameter has been considered a dimensionless quantity $B_0\to B_0M$ by setting $G = c = 1$).
• Figure 2: Metric function $\mathcal{F}(r)$ for varying values of $\alpha$ by setting $B_0=0.5$ (left) and for varying values of $B_0$ by setting $\alpha=0.4$ (right). Here, $M=1$ and $\ell_p=100$.
• Figure 3: The behavior of the effective potential for charged particle by varying $\alpha$ and $B_0$. Here $M=0.8$, $\mathrm{L}=1$, $\epsilon=0.1$, and $\ell_p=10$.
• Figure 4: A comparison of the effective potential for charge particle. Here $M=0.8$, $\mathrm{L}=1$, $\epsilon=0.1$, and $\ell_p=10$. Purple color: $\alpha=0.1, B_0=0$, blue color: $B_0=0.1, \alpha=0.1$.
• Figure 5: Plot shows trajectories of test particles around the magnetized Letelier BH in AdS spacetime for magnetic field parameter $B=0.0$ (orange curve) and $B=0.05$ (blue curve) for various combinations of angular momentum $L=3,\,4,\,5$ while keeping $\ell_p=100$ fixed, corresponding to panels from left to right. Note that top/bottom row refers to $\alpha=0.0/0.1$.