Effect of charge on anisotropic extensions of the Tolman IV solution in Rastall theory

Abstract

This study presents exact anisotropic spherical solutions for static self-gravitating systems using the extended geometric deformation scheme of gravitational decoupling within the framework of Rastall gravity. Beginning with the isotropic Tolman IV solution in the presence of an electric field, we introduce anisotropy by modifying both the temporal and radial metric potentials. This approach yields two distinct models based on the mimic pressure and mimic density constraints. We analyze the influence of the Rastall parameter, electric charge, and decoupling parameter on the extended solutions and examine key physical properties, including viability, stability, and equilibrium. For our analysis, we consider the compact stellar object SMC X-1, characterized by a mass $M=1.534\text{km}$ and a radius $I=9.34\text{km}$. Our findings indicate that both models satisfy physical viability conditions as well as stability. Additionally, we establish that the Tolman IV ansatz remains unaffected by the presence of an electric field within the Rastall gravity framework.