The High-Density Symmetry Energy and Direct Urca

Abstract

The symmetry energy of nucleonic matter is usually assumed to be quadratic in the isospin density. While this may be justified at sub-saturation densities, there is no need to enforce this restriction at super-saturation densities. The presence of a quartic term can strongly modify the critical density for the direct Urca process which leads to faster cooling of neutron stars. Neutron star cooling predictions which lie below the observational data can, for some equations of state, be repaired with a quartic term which effectively turns off the direct Urca process.

arXiv comment6 pages, 3 figures, submitted to PRC

References in corpus (20)

• Nuclear Ground-State Masses and Deformations
• The equation of state for nucleon matter and neutron star structure
• Isospin Asymmetry in Nuclei and Neutron Stars
• Composition and Structure of Protoneutron Stars
• Relativistic Mean-Field Theory and the High-Density Nuclear Equation of State
• Neutron Radii in Mean-Field Models
• Isotopic Scaling in Nuclear Reactions
• Nuclear Ground State Observables and QCD Scaling in a Refined Relativistic Point Coupling Model
• Momentum dependence of symmetry potential in asymmetric nuclear matter for transport model calculations
• Odd-Even Staggering of Nuclear Masses: Pairing or Shape Effect?
• Isospin fractionation and isoscaling in dynamical nuclear collisions
• Competition Between T=0 and T=1 Pairing in Proton-Rich Nuclei
• Constraining URCA cooling of neutron stars from the neutron radius of 208Pb
• The Origin of the Wigner Energy
• Relativistic Point-Coupling Models as Effective Theories of Nuclei
• Is there np pairing in odd-odd N=Z nuclei?
• Cooling of Akmal-Pandharipande-Ravenhall neutron star models
• Pairing and symmetry energy in N \simeq Z nuclei
• Description of rotating $N=Z$ nuclei in terms of isovector pairing
• QCD Scales in Finite Nuclei

Cited by in corpus (55)

• Recent Progress and New Challenges in Isospin Physics with Heavy-Ion Reactions
• The Nuclear Equation of State and Neutron Star Masses
• Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. XII: Stiffness and stability of neutron-star matter
• Nuclear constraints on properties of neutron star crusts
• Higher-order effects on the incompressibility of isospin asymmetric nuclear matter
• Neutrino Emission from Cooper Pairs and Minimal Cooling of Neutron Stars
• Nucleon Effective Masses in Neutron-Rich Matter
• Chiral Effective Field Theory and the High-Density Nuclear Equation of State
• Using Neutron Star Observations to Determine Crust Thicknesses, Moments of Inertia, and Tidal Deformabilities
• Isospin-dependent properties of asymmetric nuclear matter in relativistic mean-field models
• Equation of state constraints for the cold dense matter inside neutron stars using the cooling tail method
• The nuclear symmetry energy and stability of matter in neutron star
• Nuclear matter fourth-order symmetry energy in the relativistic mean field models
• Divergence of the isospin-asymmetry expansion of the nuclear equation of state in many-body perturbation theory
• The Neutron Star Crust: Nuclear Physics Input
• The Microscopic Approach to Nuclear Matter and Neutron Star Matter
• Constraints on the nuclear symmetry energy from asymmetric-matter calculations with chiral NN and 3N interactions
• Higher-order symmetry energy of nuclear matter and the inner edge of neutron star crusts
• Analytical relations between nuclear symmetry energy and single-nucleon potentials in isospin asymmetric nuclear matter
• Nuclear matter properties from local chiral interactions with $\Delta$ isobar intermediate states
• Probing isospin- and momentum-dependent nuclear effective interactions in neutron-rich matter
• Reconciling Nuclear and Astrophysical Constraints
• From the microscopic to the macroscopic world: from nucleons to neutron stars
• The isospin quartic term in the kinetic energy of neutron-rich nucleonic matter
• Nucleon self-energies for supernova equations of state
• Neutron stars and the dense matter equation of state: from microscopic theory to macroscopic observations
• Nuclear fourth-order symmetry energy and its effects on neutron star properties in the relativistic Hartree-Fock theory
• Thermal evolution of hybrid stars within the framework of a nonlocal Nambu--Jona-Lasinio model
• Neutron star cooling - a challenge to the nuclear mean field
• Exact versus Taylor-expanded energy density in the study of the neutron star crust-core transition
• Nuclear matter fourth-order symmetry energy in non-relativistic mean-field models
• Hot and Dense Homogeneous Nucleonic Matter Constrained by Observations, Experiment, and Theory
• Nuclear symmetry energy in a modified quark meson coupling model
• Empirical information on nuclear matter fourth-order symmetry energy from an extended nuclear mass formula
• Cooling of neutron stars in soft X-ray transients
• Contribution of isovector mesons to the symmetry energy in a microscopic model
• Imprints of Nuclear Symmetry Energy on Properties of Neutron Stars
• Stability of the $\beta$-equilibrated dense matter and core-crust transition in neutron stars
• Microscopic approach to the nucleon-nucleon effective interaction and nucleon-nucleon scattering in symmetric and isospin-asymmetric nuclear matter
• Constraining the nonanalytic terms in the isospin-asymmetry expansion of the nuclear equation of state
• Relationship between the symmetry energy and the single-nucleon potential in isospin-asymmetric nucleonic matter
• Dark matter admixed neutron stars with a realistic nuclear equation of state from chiral nuclear interactions
• Investigating Effects of Relativistic Kinematics, Dimensionality, Interactions, and Short-Range Correlations on the Ratio of Quartic over Quadratic Nuclear Symmetry Energies
• Anomalous quartic term in the expansion of the symmetry energy
• Influence of the nuclear symmetry energy slope on observables of compact stars with $\Delta$-admixed hypernuclear matter
• Nuclear matter properties, phenomenological theory of clustering at the nuclear surface, and symmetry energy
• From nuclear reactions to compact stars: a unified approach
• Relativistic self-energy decomposition of nuclear symmetry energy and equation of state of neutron matter within QCD sum rules
• Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions
• Nucleon Short-Range Correlations and High-Momentum Dynamics: Implications on the Equation of State of Dense Matter
• High-order isospin-dependent surface tension contribution to the fourth-order symmetry energy of finite nuclei
• Properties of glitching pulsars in the Skyrme-Hartree-Fock framework
• Isospin-Asymmetry Dependence of the Thermodynamic Nuclear Equation of State in Many-Body Perturbation Theory
• Constraining properties of neutron stars with heavy-ion reactions in terrestrial laboratories
• High-density Skyrmion matter and Neutron Stars