Collective modes in relativistic asymmetric nuclear matter

The Vlasov formalism is extended to relativistic mean field hadron models with nonlinear terms up to fourth order and applied to the calculation of the crust-core transition density. The effect of the nonlinear ωρ and σρ coupling terms on the crust-core transition density and pressure and on the macroscopic properties of some families of hadronic stars is investigated. For that purpose, six families of relativistic mean field models are considered. Within each family, the members differ in the symmetry energy behavior. For all the models, the dynamical spinodals are calculated, and the crust-core transition density and pressure and the neutron star mass-radius relations are obtained. The effect on the star radius of the inclusion of a pasta calculation in the inner crust is discussed. The set of six models that best satisfy terrestrial and observational constraints predicts a radius of 13.6 ± 0.3 km and a crust thickness of 1.36 ± 0.06 km for a 1.4M star.

Section: Discussionmentioning

confidence: 99%

“…[6][7][8]64], we express the fluctuations of the distribution functions in terms of the generating functions:…”

Section: B the Vlasov Formalismmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Vlasov formalism for extended relativistic mean field models: The crust-core transition and the stellar matter equation of state

Pais

Providência

2016

“…Considerable efforts to comprehend the uniform ground state stability of multi-component systems consisting of electrons, neutrinos, protons, and neutrons as a good approximation of this transition have been recently devoted, not only in the zero temperature approximation, but also for finite temperature [3,4,5,6,7,8,9,10,11,12]. It is obvious that in order to understand the physics inside the non-homogeneous (unstable) regions like the mechanism of nuclear creation with slab-like or rod-like shape, we have to go beyond the mean field approximation.…”

Section: Introductionmentioning

confidence: 99%

Low-density instability of multicomponent matter with trapped neutrinos

Mart

Sulaksono

2008

The effect of neutrino trapping on the longitudinal dielectric function at low densities has been investigated by using different relativistic mean field models. Parameter sets G2 of FurnstahlSerot-Tang and Z271 of Horowitz-Piekarewicz, along with the adjusted parameter sets of both models, have been used in this study. The role of the isovector adjustment and the effect of the Coulomb interaction have been also studied. The effect of the isovector adjustment is found to be more significant in the Horowitz-Piekarewicz model, not only in the neutrinoless matter, but also in the matter with neutrino trapping. Although almost independent to the variation of the leptonic fraction, the instability region of matter with neutrino trapping is found to be larger. The presence of more protons and electrons compared to the neutrinoless case is the reason behind this finding. For parameter sets with soft equation of states at low density, the appearance of a large and negative ε L (q, q 0 = 0) in some parts of the edge of the instability region in matter with neutrino trapping is understood as a consequence of the fact that the Coulomb interaction produced by electrons and protons interaction is larger than the repulsive isovector interaction created by the asymmetry between the proton and neutron numbers.

“…The equation of state of isospin asymmetric nuclear matter is a subject of particularly intense research [1,2,3,4,5]. The possible applications range from the structure of radiative nuclei, the dynamics of rare isotopes and the cooling process of neutron stars.…”

Section: Introductionmentioning

confidence: 99%

Landau parameters for isospin asymmetric nuclear matter based on a relativistic model of composite and finite extension nucleons

Aguirre

Paoli

2007

We study the properties of cold asymmetric nuclear matter at high density, applying the quark meson coupling model with excluded volume corrections in the framework of the Landau theory of relativistic Fermi liquids. We discuss the role of the finite spatial extension of composite baryons on dynamical and statistical properties such as the Landau parameters, the compressibility, and the symmetry energy. We have also calculated the low lying collective eigenfrequencies arising from the collisionless quasiparticle transport equation, considering both unstable and stable modes. An overall analysis of the excluded volume correlations on the collective properties is performed.