Equation of state effects on the core-crust interface of slow rotating neutron stars

Abstract

We systematically  study the symmetry energy  effects of the transition  density n_tand the transition pressure P_taround the crust-core interface of a neutron star in the framework of the dynamical and the thermodynamical method respectively. We employ both the parabolic approximation and the full expansion, for the definition of the symmetry energy. We use various theoretical  nuclear models. Firstly we derive and present an approximation for the transition pressure P_tand crustal mass M_crust. Secondly, we explore the effects of the Equation of State (EoS) on a few astrophysical applications which are sensitive to the values of n­_tand P_t. We found that the above quantities are sensitive mainly on the applied approximation for the symmetry energy (confirming previous results). Furthermore, an additional sensitivity also exists, depending on the used method (dynamical or thermodynamical). The above findings lead us to claim that the determination of the n­_tand P_tmust be reliable and accurate before they are used to constrain relevant neutron star properties.