Hybrid equation of state approach in binary neutron-star merger simulations

Abstract

We investigate the use of hybrid equations of state in binary neutron-star simulations in full general relativity, where thermal effects are included in an approximate way through the adiabatic index ${\Gamma }_{\mathrm{th}}$. We employ a newly developed finite-temperature equation of state derived in the Brueckner-Hartree-Fock approach and carry out comparisons with the corresponding hybrid versions of the same equation of state, investigating how different choices of ${\Gamma }_{\mathrm{th}}$ affect the gravitational-wave signal and the hydrodynamical properties of the remnant. We also perform comparisons with the widely used SFHo equation of state, detailing the differences between the two cases. Overall, we determine that when using a hybrid equation of state in binary neutron-star simulations, the value of thermal adiabatic index ${\Gamma }_{\mathrm{th}}\approx 1.7$ best approximates the dynamical and thermodynamical behaviour of matter computed using complete, finite-temperature equations of state.

15 pages, 10 figures, accepted for publication in PRD

References in corpus (19)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• A Massive Pulsar in a Compact Relativistic Binary
• Accurate evolutions of inspiralling neutron-star binaries: prompt and delayed collapse to black hole
• Binary Neutron Star Mergers: Dependence on the Nuclear Equation of State
• Spectral properties of the post-merger gravitational-wave signal from binary neutron stars
• New Hyperon Equations of State for Supernovae and Neutron Stars in Density-dependent Hadron Field Theory
• Testing Approximations of Thermal Effects in Neutron Star Merger Simulations
• On the importance of viscous dissipation and heat conduction in binary neutron-star mergers
• Recoil velocities from equal-mass binary black-hole mergers: a systematic investigation of spin-orbit aligned configurations
• High resolution numerical-relativity simulations for the merger of binary magnetized neutron stars
• THC: a new high-order finite-difference high-resolution shock-capturing code for special-relativistic hydrodynamics
• Properties of hypermassive neutron stars formed in mergers of spinning binaries
• A General-relativistic Determination of the Threshold Mass to Prompt Collapse in Binary Neutron Star Mergers
• Revisiting the lower bound on tidal deformability derived by AT 2017gfo
• When Did the Remnant of GW170817 Collapse to a Black Hole?
• Gravitational waves from remnant massive neutron stars of binary neutron star merger: Viscous hydrodynamics effects
• Hybrid protoneutron stars with the MIT bag model
• Protoneutron stars in the Brueckner-Hartree-Fock approach and finite-temperature kaon condensation
• Critical Phenomena in Neutron Stars I: Linearly Unstable Nonrotating Models

Cited by in corpus (33)

• Merger and post-merger of binary neutron stars with a quark-hadron crossover equation of state
• Realistic Finite-Temperature Effects in Neutron Star Merger Simulations
• Coalescence of black hole--neutron star binaries
• Numerical relativity simulations of prompt collapse mergers: threshold mass and phenomenological constraints on neutron star properties after GW170817
• Emergence of microphysical bulk viscosity in binary neutron star post-merger dynamics
• Thermal Effects in Binary Neutron Star Mergers
• Neural network reconstruction of the dense matter equation of state from neutron star observables
• Dense and Hot QCD at Strong Coupling
• Thermodynamical Description of Hot, Rapidly Rotating Neutron Stars, Protoneutron Stars, and Neutron Star Merger Remnants
• Degeneracy in the inference of phase transitions in the neutron star equation of state from gravitational wave data
• Impact of bulk viscosity on the post-merger gravitational-wave signal from merging neutron stars
• Binary neutron star merger simulations with hot microscopic equations of state
• Hot neutron stars and their equation of state
• Numerical modelling of bulk viscosity in neutron stars
• Microscopic nuclear equation of state at finite temperature and stellar stability
• Nuclear matter at finite temperature and static properties of proto-neutron star
• The Influence of Muons, Pions, and Trapped Neutrinos on Neutron Star Mergers
• Constraining the equation of state in neutron-star cores via the long-ringdown signal
• What if GW190425 did not produce a black hole promptly?
• Tidal Deformability Doppelgangers: Implications of a low-density phase transition in the neutron star equation of state
• Effects of Onset of Phase Transition on Binary Neutron Star Mergers
• Finite-temperature effects in dynamical-spacetime binary neutron star merger simulations: Validation of the parametric approach
• Equation of state of neutron star matter and its warm extension with an interacting hadron resonance gas
• Signature of hadron-quark crossover in binary-neutron-star mergers
• Neutron Stars and Gravitational Waves: the Key Role of Nuclear Equation of State
• Accurate nuclear symmetry energy at finite temperature within a BHF approach
• Modeling Neutron Star Matter in the Age of Multimessenger Astrophysics
• Thermal effects on nuclear matter properties
• Investigating the Impact of Higher-Order Phase Transitions in Binary Neutron-Star Mergers
• Dependence of postmerger properties on the thermal heating efficiency in neutron star mergers
• $f$-mode oscillations of compact stars with realistic equations of state in dynamical spacetime
• Thermal aspects of neutron star mergers
• Nuclear Matter and Finite Nuclei: Relativistic Thomas-Fermi Approximation Versus Relativistic Mean-Field Approach