We extend the relativistic mean field theory model of Sugahara and Toki by adding new couplings suggested by modern effective field theories. An improved set of parameters is developed with the goal to test the ability of the models based on effective field theory to describe the properties of finite nuclei and, at the same time, to be consistent with the trends of Dirac-Brueckner-Hartree-Fock calculations at densities away from the saturation region. We compare our calculations with other relativistic nuclear force parameters for various nuclear phenomena.

Surface and curvature properties of asymmetric semi-infinite nuclear matter are studied to beyond the proton drip. Using the semiclassical extended Thomas-Fermi method, the calculations are performed in the non-relativistic and relativistic mean field theories (Skyrme forces and non-linear σ−ω parametrizations). First we discuss the bulk equilibrium between the nuclear and drip phases. Next we analyze the asymmetric surface as a function of the bulk neutron excess. We examine local quantities related to the density profiles and, for two definitions of the bulk reference energy, the surface and curvature energy coefficients. The calculation of the curvature energy is carefully treated. The sensitivity of the nuclear surface to the relativistic effects is investigated. Mass formulae useful for arbitrary neutron excess are discussed, and their limit at small asymmetries is compared with the liquid droplet model mass formula.

By using the scaling method and the Thomas-Fermi and extended Thomas-Fermi approaches to relativistic mean field theory the surface contribution to the leptodermous expansion of the finite nuclei incompressibility K A has been self-consistently computed. The validity of the simplest expansion, which contains volume, volume-symmetry, surface, and Coulomb terms, is examined by comparing it with self-consistent results of K A for some currently used nonlinear -parameter sets. A numerical estimate of higher-order contributions to the leptodermous expansion, namely, the curvature and surface-symmetry terms, is made. DOI: 10.1103/PhysRevC.65.044304 PACS number͑s͒: 24.30.Cz, 21.60.Ϫn, 21.30.Fe The curvature of the nuclear matter equation of state, i.e., the nuclear matter incompressibility K ϱ is a key quantity in nuclear physics because it is related to many properties of nuclei ͑such as radii, masses, and giant resonances͒, heavyion collisions, neutron stars, and supernova collapses. One important source of information on K ϱ is provided by the study of the isoscalar giant monopole resonance ͑GMR͒ ͑breathing mode͒ in finite nuclei. In the nonrelativistic frame, theoretical microscopic calculations based on the randomphase approximation ͓1͔ and approximations to it such as the scaling method ͓2-4͔ or constrained calculations ͓3-5͔ using Skyrme ͓3͔ and Gogny ͓6͔ effective forces lead to a nuclear matter incompressibility coefficient K ϱ of 215Ϯ15 MeV ͓6,7͔. A similar analysis carried out within the relativistic mean field ͑RMF͒ theory with nonlinear -effective Lagrangians gives a value of K ϱ slightly higher, that is, 250-270 MeV ͓8͔.The nuclear matter incompressibilty K ϱ is not a directly measurable quantity; what is measured is, actually, the energy E M of the GMR of finite nuclei. It is convenient to write this energy in terms of the incompressibility K A for a finite nucleus of mass number A aswhere ͗r 2 ͘ is the rms matter radius and M the nucleon mass.The finite nucleus incompressibilty K A can be parametrized by means of a leptodermous expansion ͓2͔ that is similar to the liquid drop mass formulawhere Iϭ(NϪZ)/A is the neutron excess. Equation ͑2͒ suggests that it is possible to fit the coefficients of the expansion to the experimental data in a model independent way. Although some effort along these lines has been made in the past ͓9͔, the fact that a fit of the parameters of Eq. ͑2͒ to experimental data does not lead to a unique determination of the parameters is well established ͓6,10,11͔. Rather, the nuclear matter incompressibility has to be determined from effective forces that reproduce, in a microscopic calculation, the experimental values of the GMR excitation energy in heavy nuclei ͓6͔.It is also possible to fit K A calculated microscopically within the scaling model for a given effective interaction to the leptodermous expansion Eq. ͑2͒. This has been done, for example, in the nonrelativistic frame using Skyrme forces ͓12͔. In this case the coefficients entering Eq. ͑2͒ can be expressed through in...

We perform Hartree calculations of symmetric and asymmetric semi-infinite nuclear matter in the framework of relativistic models based on effective hadronic field theories as recently proposed in the literature. In addition to the conventional cubic and quartic scalar self-interactions, the extended models incorporate a quartic vector self-interaction, scalar-vector non-linearities and tensor couplings of the vector mesons. We investigate the implications of these terms on nuclear surface properties such as the surface energy coefficient, surface thickness, surface stiffness coefficient, neutron skin thickness and the spin-orbit force.Comment: 30 pages, 15 figures. Submitted to Nuclear Physics

We derive analytical expressions for the excitation energy of the isoscalar giant monopole and quadrupole resonances in finite nuclei, by using the scaling method and the extended Thomas-Fermi approach to relativistic mean field theory. We study the