Modeling anisotropic compact stars in f(R,G,T) gravity through a singularity-free approach

We investigate compact stellar configurations in the framework of [Formula: see text] gravity, where [Formula: see text], [Formula: see text], and [Formula: see text] denote the Ricci scalar, Gauss–Bonnet invariant term, and trace of the energy–momentum tensor, respectively. Adopting a linear functional form [Formula: see text], we explore the combined influence of higher-order curvature corrections ([Formula: see text]) and matter–geometry coupling ([Formula: see text]). Assuming a static, spherically symmetric spacetime with anisotropic matter distribution, we obtain exact and regular solutions to the modified field equations using the Krori–Barua metric ansatz. Model parameters are constrained with observational inputs from the LMXB neutron star 4U 1608-52, characterized by mass [Formula: see text] and radius [Formula: see text]. We analyze three representative cases: negative [Formula: see text], null [Formula: see text] corresponding to General Relativity, and positive [Formula: see text] values of [Formula: see text]. The resulting solutions satisfy all standard physical requirements, including causality condition, energy conditions and stability criteria. An effective equation of state is constructed via a curve-fitting procedure by optimizing the central sound speed. Employing the Buchdahl compactness limit and a central density [Formula: see text], we estimate the maximum mass and radius. Notably, the model predicts a maximum mass up to [Formula: see text] for [Formula: see text], and may be utilized to study the properties of primary mass [Formula: see text] detected in the gravitational wave event GW230529_181500. By varying the central density, the model reproduces radii consistent with many observed pulsars and recent gravitational wave events. These results demonstrate that the proposed framework provides stable configurations and offers a consistent extension of General Relativity for probing the internal structure of compact stars.