Low density nuclear matter with quantum molecular dynamics : The role of the symmetry energy

Abstract

We study the effect of isospin-dependent nuclear forces on the pasta phase in the inner crust of neutron stars. To this end we model the crust within the framework of quantum molecular dynamics (QMD). For maximizing the numerical performance, a newly developed code has been implemented on GPU processors. As a first application of the crust studies we investigate the dependence of the particular pasta phases on the isospin dependence of the interaction, including non-linear terms in this sector of the interactions. Our results indicate that in contrast to earlier studies the phase diagram of the pasta phase is not very sensitive to isospin effects. We show that the extraction of the isospin parameters like asymmetry energy and slope from numerical data is affected by higher-order terms in the asymmetry dependence of the energies per particle. Furthermore, a rapid transition from the pasta to a homogeneous phase is observed even for proton-to-neutron ratios typical for a supernova environment.

19 pages, 9 figures

References in corpus (12)

• Neutron Star Observations: Prognosis for Equation of State Constraints
• The Breaking Strain of Neutron Star Crust and Gravitational Waves
• Higher-order effects on the incompressibility of isospin asymmetric nuclear matter
• Disordered nuclear pasta, magnetic field decay, and crust cooling in neutron stars
• The symmetry energy at subnuclear densities and nuclei in neutron star crusts
• Simulation of Transitions between "Pasta" Phases in Dense Matter
• Formation of Nuclear "Pasta" in Supernovae
• Nuclear matter in the crust of neutron stars
• Nuclear Waffles
• Influence of the symmetry energy on nuclear pasta in neutron star crusts
• The Shear Viscosity and Thermal Conductivity of Nuclear Pasta
• Finite size effects in Neutron Star and Nuclear matter simulations

Cited by in corpus (17)

• Quantum Nuclear Pasta and Nuclear Symmetry Energy
• Impact of the neutron-star deformability on equation of state parameters
• Nuclear fourth-order symmetry energy and its effects on neutron star properties in the relativistic Hartree-Fock theory
• Transport properties of nuclear pasta phase with quantum molecular dynamics
• Domains and defects in nuclear "pasta"
• Role of crustal physics in the tidal deformation of a neutron star
• Glassy quantum nuclear pasta in neutron star crusts
• Nuclear matter fourth-order symmetry energy in non-relativistic mean-field models
• Empirical information on nuclear matter fourth-order symmetry energy from an extended nuclear mass formula
• Nuclear pasta and supernova neutrinos at late times
• Thermal Fluctuations in Nuclear Pasta
• Anomalous quartic term in the expansion of the symmetry energy
• Relativistic self-energy decomposition of nuclear symmetry energy and equation of state of neutron matter within QCD sum rules
• Accurate nuclear symmetry energy at finite temperature within a BHF approach
• Effect of the Coulomb interaction on the liquid-gas phase transition of nuclear matter
• Aspects of approximation in modelling of the symmetry energy
• Low Density Neutron Star Matter with Quantum Molecular Dynamics: The Role of Vector Interactions