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Experimental giant monopole resonance energies are now known to constrain nuclear incompressibility of symmetric nuclear matter K and its density slope M at a particular value of subsaturation density, the crossing density ρc. Consistent with these constraints, we propose a reasonable way to construct a plausible equation of state of symmetric nuclear matter in a broad density region around the saturation density ρ0. Help of two additional empirical inputs, the value of ρ0 and that of the energy per nucleon e(ρ0) are needed. The value of K(ρ0) comes out to be 211.9±24.5 MeV. [ABSTRACT FROM AUTHOR]

In multifragmentation of hot nuclear matter, properties of fragments embedded in a soup of nucleonic gas and other fragments should be modified as compared with isolated nuclei. Such modifications are studied within a simple model where only nucleons and one kind of heavy nuclei are considered. The interaction between different species is described with a momentum-dependent two-body potential whose parameters are fitted to reproduce properties of cold isolated nuclei. The internal energy of heavy fragments is parametrized according to a liquid-drop model with density- and temperature-dependent parameters. Calculations are carried out for several subnuclear densities and moderate temperatures, for isospin-symmetric and asymmetric systems. We find that the fragments get stretched due to interactions with the medium and their binding energies decrease with increasing temperature and density of nuclear matter. [ABSTRACT FROM AUTHOR]

The temperature dependence of the symmetry energy and the symmetry free energy coefficients of atomic nuclei is investigated in a finite temperature Thomas-Fermi framework employing the subtraction procedure. A substantial decrement in the symmetry energy coefficient is obtained for finite systems, contrary to those seen for infinite nuclear matter at normal and somewhat subnormal densities. The effect of the coupling of the surface phonons to the nucleonic motion is also considered; this is found to decrease the symmetry energies somewhat at low temperatures. [ABSTRACT FROM AUTHOR]

The properties of warm dilute α-nucleon matter are studied in a variational approach in the Thomas-Fermi approximation starting from an effective two-body nucleon-nucleon interaction. The equation of state, symmetry energy, incompressibility of the said matter, and α fraction are in consonance with those evaluated from the virial approach, which sets the benchmark for such calculations at low densities. [ABSTRACT FROM AUTHOR]

Empirically determined values of the nuclear volume and surface symmetry energy coefficients from nuclear masses are expressed in terms of density distributions of nucléons in heavy nuclei in the local density approximation. This is then used to extract the value of the symmetry energy slope parameter L. The density distributions in both spherical and well deformed nuclei calculated within microscopic framework with different energy density functionals give L = 59.0 ± 13.0 MeV. Application of the method also helps in a precision determination of the neutron skin thickness of nuclei that are difficult to measure accurately. [ABSTRACT FROM AUTHOR]

From empirically determined values of some of the characteristic constants associated with homogeneous nuclear matter at saturation and subsaturation densities, within the framework of a Skyrme-inspired energy density functional, we construct an equation of state (EoS) of nuclear matter. This EoS is then used to predict values of density slope parameters of symmetry energy L(ρ), isoscalar incompressibility K(ρ), and a few related quantities. The close consonance of our predicted values with the currently available ones for the density dependence of symmetry energy and incompressibility gleaned from diverse approaches offers the possibility that our method may help in settling their values in tighter bounds. Extrapolation of our EoS at supranormal densities shows that it is in good harmony with the one extracted from experimental data. [ABSTRACT FROM AUTHOR]

The thermal evolution of a few thermodynamic properties of the nuclear surface like its thermodynamic potential energy, entropy, and the symmetry free energy are examined for both semi-infinite nuclear matter and finite nuclei. The Thomas-Fermi model is employed. Three Skyrme interactions, namely, SkM*, SLy4, and SK255, are used for the calculations to gauge the dependence of the nuclear surface properties on the energy density functionals. For finite nuclei, the surface observables are computed from a global liquid-drop-inspired fit of the energies and free energies of a host of nuclei covering the entire periodic table. The hot nuclear system is modeled in a subtracted Thomas-Fermi framework. Compared to semi-infinite nuclear matter, substantial changes in the surface symmetry energy of finite nuclei are indicated; surface thermodynamic potential energies for the two systems are, however, not too different. Analytic expressions to fit the temperature and asymmetry dependence of the surface thermodynamic potential of semi-infinite nuclear matter and the temperature dependence of the surface free energy of finite nuclei are given. [ABSTRACT FROM AUTHOR]