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Title: Relativistic mean-field model with energy dependent self-energies

Abstract

Conventional relativistic mean-field theory is extended with the introduction of higher-order derivative couplings of nucleons with the meson fields. The Euler-Lagrange equations follow from the principle of stationary action. From invariance principles of the Lagrangian density the most general expressions for the conserved current and energy-momentum tensor are derived. The nucleon self-energies show the explicit dependence on the meson fields. They contain additional regulator functions which describe the energy dependence. The density dependence of meson-nucleon couplings causes the apperance of additional rearrangement contributions in the self-energies. The equation of state of infinite nuclear matter is obtained and the thermodynamical consistency of the model is demonstrated. This model is applied to the description of spherical, non-rotating stars in β-equilibrium. Stellar structure is calculated by solving the Tolman-Oppenheimer-Volkov (TOV) equations. The results for neutron stars are shown in terms of mass-radius relations.

Authors:
;  [1]
  1. GSI Helmholtzzentrum fur Schwerionenforschung GmbH, Darmstadt (Germany)
Publication Date:
OSTI Identifier:
22390982
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1645; Journal Issue: 1; Conference: Carpathian Summer School of Physics 2014, Sinaia (Romania), 13-26 Jul 2014; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
73 NUCLEAR PHYSICS AND RADIATION PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ENERGY DEPENDENCE; ENERGY-MOMENTUM TENSOR; EQUATIONS OF STATE; INVARIANCE PRINCIPLES; LAGRANGE EQUATIONS; LAGRANGIAN FUNCTION; MEAN-FIELD THEORY; MESONS; NEUTRON STARS; NUCLEAR MATTER; NUCLEONS; RELATIVISTIC RANGE; SELF-ENERGY; STAR MODELS

Citation Formats

Antic, S., and Typel, S.. Relativistic mean-field model with energy dependent self-energies. United States: N. p., 2015. Web. doi:10.1063/1.4909585.
Antic, S., & Typel, S.. Relativistic mean-field model with energy dependent self-energies. United States. doi:10.1063/1.4909585.
Antic, S., and Typel, S.. Tue . "Relativistic mean-field model with energy dependent self-energies". United States. doi:10.1063/1.4909585.
@article{osti_22390982,
title = {Relativistic mean-field model with energy dependent self-energies},
author = {Antic, S. and Typel, S.},
abstractNote = {Conventional relativistic mean-field theory is extended with the introduction of higher-order derivative couplings of nucleons with the meson fields. The Euler-Lagrange equations follow from the principle of stationary action. From invariance principles of the Lagrangian density the most general expressions for the conserved current and energy-momentum tensor are derived. The nucleon self-energies show the explicit dependence on the meson fields. They contain additional regulator functions which describe the energy dependence. The density dependence of meson-nucleon couplings causes the apperance of additional rearrangement contributions in the self-energies. The equation of state of infinite nuclear matter is obtained and the thermodynamical consistency of the model is demonstrated. This model is applied to the description of spherical, non-rotating stars in β-equilibrium. Stellar structure is calculated by solving the Tolman-Oppenheimer-Volkov (TOV) equations. The results for neutron stars are shown in terms of mass-radius relations.},
doi = {10.1063/1.4909585},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1645,
place = {United States},
year = {Tue Feb 24 00:00:00 EST 2015},
month = {Tue Feb 24 00:00:00 EST 2015}
}
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