The neutron star inner crust and symmetry energy

The cell structure of clusters in the inner crust of a cold \beta-equilibrium neutron star is studied within a Thomas Fermi approach and compared with other approaches which include shell effects. Relativistic nuclear models are considered. We conclude that the symmetry energy slope L may have quite dramatic effects on the cell structure if it is very large or small. Rod-like and slab-like pasta clusters have been obtained in all models except one with a large slope L.Comment: 16 pages, 5 figure

Light Clusters and Pasta Phases in Warm and Dense Nuclear Matter

The pasta phases are calculated for warm stellar matter in a framework of relativistic mean-field models, including the possibility of light cluster formation. Results from three different semiclassical approaches are compared with a quantum statistical calculation. Light clusters are considered as point-like particles, and their abundances are determined from the minimization of the free energy. The couplings of the light-clusters to mesons are determined from experimental chemical equilibrium constants and many-body quantum statistical calculations. The effect of these light clusters on the chemical potentials is also discussed. It is shown that including heavy clusters, light clusters are present until larger nucleonic densities, although with smaller mass fractions.Comment: 15 pages, 13 figures, accepted for publication in Physical review

Light pseudoscalar meson masses under strong magnetic fields within the SU(3) Nambu-Jona-Lasinio model

We calculate the pole masses of pseudoscalar mesons in a strongly magnetized medium within the framework of the SU(3) Nambu-Jona-Lasinio model, using a magnetic field-independent regularization scheme. We employ both a constant and a magnetic field-dependent coupling G(B), the latter being fitted to reproduce lattice QCD results for the pseudocritical chiral transition temperature. Numerical results for the pole masses are obtained for definite parametrizations of the model. For neutral mesons, the use of G(B) provides closer agreement with lattice QCD results, which reveal a decrease of the mass with the external field. On the contrary, charged mesons masses are enhanced by B, showing no sign of the nonmonotonous behavior found in recent lattice QCD simulations.Fil: Avancini, Sidney S.. Universidade Federal Da Santa Catarina. Cent.de Cs Físicas E Matemáticas; BrasilFil: Sodre, Joanna. Universidade Federal Da Santa Catarina. Cent.de Cs Físicas E Matemáticas; BrasilFil: Coppola, Máximo. Comisión Nacional de Energía Atómica. Gerencia de Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (CAB); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Scoccola, Norberto Nerio. Comisión Nacional de Energía Atómica. Gerencia de Área de Investigaciones y Aplicaciones No Nucleares. Gerencia de Física (CAB); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin