A Density-dependent van der Waals Model under the GW170817 Constraint

Abstract

We propose a density-dependent function for the attractive interaction in the original van der Waals model to correctly describe the flow constraint at the high-density regime of the symmetric nuclear matter. After a generalization to asymmetric nuclear matter, it was also possible to study the stellar matter regime from this new model. The mass–radius relation for neutron stars under β -equilibrium is found to agree with recent X-ray observations. The neutron-star masses supported against gravity, obtained from some parameterizations of the model, are in the range of (1.97–2.07) M ⊙ , compatible with observational data from the PSR J0348+0432 pulsar. Furthermore, we verify the reliability of the model in predicting tidal deformabilities of the binary system related to the GW170817 neutron-star merger event and find a full agreement with the new bounds obtained by the LIGO/Virgo collaboration.