Compression modulus and symmetry energy of nuclear matter with KIDS density functional

Parametrization of the Relativistic ($σ-ω$) Model for Nuclear Matter

We have investigated the zero-temperature equation of state (EoS) for infinite nuclear matter within the $(σ-ω)$ model at all densities $n_{\mathrm{B}}$ and different proton-neutron asymmetry $η\equiv(N-Z)/A$. We have presented an analytical expression for the compression modulus and found that nuclear matter ceases to saturate at $η$ slightly larger than $0.8$. Afterward, we have developed an analytical method to determine the strong coupling constants from the EoS for isospin symmetric nuclear matter, which allow us to reproduce all the saturation properties with high accuracy. For various v…

Unmasking the nuclear matter equation of state

Accurately calibrated (or ``best fit'') relativistic mean-field models are used to compute the distribution of isoscalar monopole strength in 90Zr and 208Pb, and the isovector dipole strength in 208Pb using a continuum random-phase-approximation approach. It is shown that the distribution of isoscalar monopole strength in 208Pb--but not in 90Zr--is sensitive to the density dependence of the symmetry energy. This sensitivity hinders the extraction of the compression modulus of symmetric nuclear matter from the isoscalar giant monopole resonance (ISGMR) in 208Pb. Thus, one relies on 90Zr, a nucl…

Relativistic Hartree-Fock theory. Part I: density-dependent effective Lagrangians

Effective Lagrangians suitable for a relativistic Hartree-Fock description of nuclear systems are presented. They include the 4 effective mesons $σ, ω, ρ$ and $π$ with density-dependent meson-nucleon couplings. The criteria for determining the model parameters are the reproduction of the binding energies in a number of selected nuclei, and the bulk properties of nuclear matter (saturation point, compression modulus, symmetry energy). An excellent description of nuclear binding energies and radii is achieved for a range of nuclei encompassing light and heavy systems. The predictions of the pres…

Nuclear incompressibility in the quasilocal density functional theory

We explore the ability of the recently established quasilocal density functional theory for describing the isoscalar giant monopole resonance. Within this theory we use the scaling approach and perform constrained calculations for obtaining the cubic and inverse energy weighted moments (sum rules) of the RPA strength. The meaning of the sum rule approach in this case is discussed. Numerical calculations are carried out using Gogny forces and an excellent agreement is found with HF + RPA results previously reported in literature. The nuclear matter compression modulus predicted in our model lie…

Finite volume of baryons and the mass limit for neutron stars

We confirmed the following idea by numerical calculation: The extended structure of baryons may make the nuclear equation of state stiffer at higher density while keeping the compression modulus for normal nuclear matter around its empirical value $K=240MeV$.The model built in this wayy fits all empirical data for normal nuclear matter and gives the mass limit of neutron stars compatible with the observation.

Relativistic Ring-Diagram Nuclear Matter Calculations

A relativistic extension of the particle-particle hole-hole ring-diagram many-body formalism is developed by using the Dirac equation for single-particle motion in the medium. Applying this new formalism, calculations are performed for nuclear matter. The results show that the saturation density is improved and the equation of state becomes softer as compared to corresponding Dirac-Brueckner-Hartree-Fock calculations. Using the Bonn A potential, nuclear matter is predicted to saturate at an energy per nucleon of --15.30 MeV and a density equivalent to a Fermi momentum of 1.38 fm$^{-1}$, in exc…

Light Front Theory Of Nuclear Matter

A relativistic light front formulation of nuclear dynamics is applied to infinite nuclear matter. A hadronic meson-baryon Lagrangian, consistent with chiral symmetry, leads to a nuclear eigenvalue problem which is solved, including nucleon-nucleon (NN) correlations, in the one-boson-exchange approximation for the NN potential. The nuclear matter saturation properties are reasonably well reproduced, with a compression modulus of 180 MeV. We find that there are about 0.05 excess pions per nucleon.

单极激发与核压缩性：现状与未来展望

Monopole Excitation and Nuclear Compressibility: Present and Future Perspectives

本文综述核单极共振与核压缩性研究现状，指出当前模型无法统一描述闭壳与开壳核数据的问题，提出需获取宽$N/Z$比同位素链的新实验数据以更精确测定核物质不可压缩性与对称能。

On the Density Dependent Nuclear Matter Compressibility

In the present work we apply a quantum hadrodynamic effective model in the mean-field approximation to the description of neutron stars. We consider an adjustable derivative-coupling model and study the parameter influence on the dynamics of the system by analyzing the full range of values they can take. We establish a set of parameters which define a specific model that is able to describe phenomenological properties such as the effective nucleon mass at saturation as well as global static properties of neutron stars (mass and radius). If one uses observational data to fix the maximum mass fo…

In-medium meson effects on the equation of state of hot and dense nuclear matter

The influence of the in-medium mesons on the effective nucleon mass and in turn on the equation of state of hot/dense nuclear matter is discussed in the Walecka model. Due to the self-consistent treatment of couplings between nucleons and $σ$ and $ω$ mesons, the temperature and density dependence of the effective hadron masses approaches more towards the Brown-Rho scaling law, and the compression modulus $K$ is reduced from $550 MeV$ in mean field theory to an accepted value $318.2 MeV$.