Gravitational Collapse of Anisotropic Compact Stars in Modified $ f(R) $ Gravity

Abstract

The physically realistic model of compact stars undergoing gravitational collapse in $ f(R) $ gravity has been developed. We consider a more general model $ R + f(R) = R + k R^m $ and describe the interior space-time of gravitationally collapsing stars with separable-form of metric admitting homothetic killing vector. We then investigate the junction conditions to match the interior space-time with exterior space-time. Considering all junction conditions, we find analytical solutions describing interior space-time metric, energy density, pressures, and heat flux density of the compact stars undergoing gravitational collapse. We impose the energy conditions to the model for describing the realistic collapse of physically possible matter distribution for particular models of $GR$, $ R+k R^2 $ and $ R+k R^4 $ gravity. The comprehensive graphical analysis of all energy conditions show that the model is physically acceptable and realistic. We additionally investigate the physical properties of collapsing stars which are useful to decipher the inherent nature of such gravitationally collapsing stars.