A new model of quintessence compact stars in the Rastall theory of gravity

Abstract.

In the present work, we study a new model of anisotropic compact stars in the regime of the Rastall theory. To solve the Rastall field equations we have used the Karori and Barua (KB) ansatz along with the quintessence dark energy characterized by a parameter $\omega_{q}$ with $-1 < \omega_{q} < -\frac{1}{3}$. We present a comparative study to demonstrate the physical acceptance of our proposed model. We compare the numerical values of physical parameters obtained from our model with those of the general relativity (GR model given by Bhar (Astrophys. Space Sci. 356, 309 (2015)) and observe that our model is more compatible (for some chosen values of Rastall dimensionless parameter $\gamma = \kappa\lambda$ with observational data than the GR model. For this analysis we have considered four different compact stars, SAXJ 1808 - 3658 (SSI), 4U 1820 - 30 , VelaX -12 and PSRJ 1416 - 2230 with radii 7.07 km, 10 km, 9.99 km and 10.3 km, respectively. In this investigation we also present some physical aspects of the proposed model necessary to check the validity of the model and infer that our model is acceptable physically and geometrically.