Quark stars in Rastall gravity with recent astrophysical observations

Abstract

Advanced observational astronomy suggests that the density inside neutron stars is several times higher than the saturation density of nuclear matter. At such high densities, physicists speculate on the presence of quark matter inside the neutron stars. However, obtaining the exact equation of state of quark matter reliably remains elusive. This motivates us to consider a generic MIT bag model for the quark matter equation of state to investigate the internal composition of compact stars in these extreme environments. For the background static and spherically symmetric solutions, we describe quark stars within the framework of Rastall gravity theory. Specifically, we analyze the mass-radius relation and the corresponding stability of quark stars depending on model parameters such as a(2), a(4), and the Rastall parameter eta. We conclude by discussing the predictability of such a model with existing results from different high-precision timing datasets of three-millisecond pulsars and GW events, such as GW170817 associated with a binary neutron star merger.