Study of tidal deformabilities of neutron stars using relativistic mean field theory containing <i>δ</i> mesons

Abstract

The research on the macroscopic properties of neutron stars is of great significance in revealing the internal composition and structure of neutron star. In this work, We analyze the influence of <i>δ</i> mesons on the equation of states, the maximum mass, the tidal Love numbers and the tidal deformabilities for the conventional neutron stars and the hyperon stars within the relativistic mean field theory. It is found that the presence of <i>δ</i> mesons can strengthen the tidal deformabilities of the low and medium-mass conventional neutron stars (or hyperon stars). However, the strengthening trends of the tidal deformabilities with <i>δ</i> mesons gradually weaken with the increase of the mass of the conventional neutron stars (or hyperon stars). Especially for massive hyperon stars, the tidal deformabilities of the superstars with <i>δ</i> mesons is weaker than the corresponding values without <i>δ</i> mesons. Moreover, the presence of hyperons can reduce the tidal deformabilities of stars with the same mass. For the stars containing <i>δ</i> mesons, only the tidal deformabilities in the hyperon stars with <i>Λ</i>, <i>Σ</i> and <i>Ξ</i> hyperons can satisfy the constraints of GW170817 and GW190814 events under the parameters selected in the paper. As the data about gravitational waves associated with the neutron stars gradually increase, there will be a possible way of judging the hyperon species in the hyperon stars.