Analysis of charged compact stars by core-envelope model in f(R, T) gravity

In this manuscript, we explore two static and spherically symmetric, anisotropic, charged stars employing the formalism of modified f ( R, T ) gravity, where the gravitational Lagrangian is taken as f ( R , T ) = R + 2 γ T . By introducing a core-envelope structure, we bring a new dimension to stellar modeling in modified gravity. Where the core follows a polytropic equation of state (EoS) and the envelope is modeled linearly. The internal spacetime continuously matched to the exterior Reissner–Nordstr o ¨ m spacetime at the surface. We incorporate the effects of matter-geometry coupling by analyzing the physical quantities for three values of the coupling constant γ , offering new insights into how such coupling (associated with dark matter effects) influence stellar behavior. To validate the physical acceptability of the model, we examine key physical parameters and stability criteria, including density, pressure profiles, energy conditions, causality constraints, and the modified Tolman–Oppenheimer–Volkoff (TOV) equation. The stability of the model is further evaluated by the adiabatic index for astrophysical objects S A X J 1808.4 − 3658 , 4 U 1608 − 52 . Our results demonstrate that the proposed model is physically free from singularity, and sensitive to the matter-geometry coupling. The significance of f ( R, T ) gravity in star’s modeling is highlighting with possible dark matter effects.