Saturation Properties and Density-dependent Interactions among Nuclear and Hyperon Matter

ABSTRACT

The density-dependent interrelations among properties of nuclear matter and hyperonic neutron stars are studied by applying the conserving nonlinear mean-field theory of hadrons. The nonlinear interactions that will be renormalized as effective coupling constants, effective masses and sources of equations of motion are constructed selfconsistently by maintaining thermodynamic consistency (the Hugenholtz-Van Hove theorem, conditions of conserving approximations) to the nonlinear mean-field (Hartree) approximation. The characteristic density-dependent properties among nuclear matter and hyperonic neutron stars appear by way of effective coupling constants and masses of hadrons; they are mutually interdependent and self-consistently constrained via the bulk properties of infinite matter, such as incompressibility, K, symmetry energy, α⁴, and maximum masses of neutron stars. Consequently, the densitydependence induced by nonlinear interactions of hadrons will determine and restrict the saturation properties (binding energy and density) of hyperons, hyperon-onset density and equation of state in high densities. The nonlinear hadronic mean-field and quark-based hadronic models will predict essentially different density-dependent behavior for hadrons in terms of effective masses and coupling constants, and discrepancies between the models are shown and discussed, which would improve and compensate for both approaches to nuclear physics.