Recent Progress in Neutron Star Theory

This review contains chapters discussing: Energy density fluctionals of nuclear matter, Many-body theory of nucleon matter, Hadronic and quark matter, Mixtures of phases in dense matter, Neutron star observations and predictions.Comment: 33 pages +13 figs., Ann. Rev. Nucl. & Part. Science, 200

TRANSITION CHARGE-DENSITIES OF LOW-LYING COLLECTIVE STATES IN PT 196 FROM INELASTIC ELECTRON-SCATTERING

Differential cross sections for levels in the excitation-energy range from 0 to 3.0 MeV in Pt-196 have been measured by inelastic electron scattering in a momentum-transfer range up to 2.5 fm-1. The ground-state charge density and the transition charge densities of nine low-lying collective levels have been extracted in a Fourier-Bessel analysis of these data. The densities are compared with those obtained from microscopic calculations within the quasiparticle phonon model, using the single-particle basis obtained from a density functional approach. Satisfactory agreement has been obtained, in spite of the complicated structure of Pt-196

Real- and Complex-Energy Non-conserving Particle Number Pairing Solution

Many-body open quantum systems are characterized by the correlations between bound and scattering states. In contrast to a closed system (i.e., a very well bound many-body system), the continuous part of the energy spectrum has to be considered explicitly due to the proximity of the Fermi level to the continuums threshold. In this work we show how to introduce these correlations through the continuum single-particle level density (CSPLD) in the pairing framework. By isolating the resonances of the system using an analytic continuation, we arrive at the Berggren (complex-energy) representation of the pairing solutionFil: Id Betan, Rodolfo Mohamed. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Rosario. Instituto de Física de Rosario. Universidad Nacional de Rosario. Instituto de Física de Rosario; Argentin

Nuclear Equation of state for Compact Stars and Supernovae

International audienceThe equation of state (EoS) of hot and dense matter is a fundamental input to describe static and dynamical properties of neutron stars, core-collapse supernovae and binary compact-star mergers. We review the current status of the EoS for compact objects, that have been studied with both ab-initio many-body approaches and phenomenological models. We limit ourselves to the description of EoSs with purely nucleonic degrees of freedom, disregarding the appearance of strange baryonic matter and/or quark matter. We compare the theoretical predictions with different data coming from both nuclear physics experiments and astrophysical observations. Combining the complementary information thus obtained greatly enriches our insights into the dense nuclear matter properties. Current challenges in the description of the EoS are also discussed, mainly focusing on the model dependence of the constraints extracted from either experimental or observational data (specifically, concerning the symmetry energy), the lack of a consistent and rigorous many-body treatment at zero and finite temperature of the matter encountered in compact stars (e.g. problem of cluster formation and extension of the EoS to very high temperatures), the role of nucleonic three-body forces, and the dependence of the direct URCA processes on the EoS