Role of decoupling and Rastall parameters on Krori–Barua and Tolman IV models generated by isotropization and complexity factor

Abstract We develop multiple analytical solutions to the Rastall field equations using a recently proposed scheme, named the gravitational decoupling. In order to do this, we assume a spherical distribution that possesses anisotropic pressure in its interior and extend it by incorporating an additional gravitating source through the corresponding Lagrangian density. Such addition in the initial fluid distribution leads to the complicated field equations which are then tackled by implementing the minimal geometric deformation. This execution divides these equations into two different systems, each corresponds to the original source. The first system representing initial source is solved by adopting Krori–Barua and Tolman IV spacetimes, while three different constraints are used to work out the other set. The constants engaged in the above two ansatz are calculated through the junction conditions. The developed models are further explored graphically in the interior of a star, say <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mn>4</mml:mn> <mml:mi>U</mml:mi> <mml:mn>1820</mml:mn> <mml:mo>−</mml:mo> <mml:mn>30</mml:mn> </mml:mrow> </mml:math> . Finally, we conclude our results to be physically feasible under the considered variation in both Rastall and decoupling parameters. It is important to mention here that the derived models can be viewed as idealized or toy models that serve as preliminary explorations within the framework of Rastall gravity.