Quark-nuclear hybrid equation of state for neutron stars under modern observational constraints

Abstract

We study a family of equations of state for hybrid neutron star matter. The hybrid EOS are obtained by a Maxwell construction of the first-order phase transition between a hadronic phase described by the relativistic density-functional EOS of the "DD2" class with excluded volume effects and a deconfined quark matter phase modeled by an instantaneous nonlocal version of the Nambu-Jona-Lasinio model in SU(2)${}_f$ with vector interactions and color superconductivity. The form factor in the nonlocal quark matter model is fitted to lattice QCD results in the Coulomb gauge. Owing to strong coupling in the vector meson and diquark channels, a coexistence phase of color superconductivity and chiral symmetry breaking occurs. Our results show an approximately constant behavior for the squared speed of sound with values of 0.4 - 0.6 in the density region relevant for neutron star interiors. To simultaneously fulfill the constraints from the Neutron Star Interior Composition Explorer radius measurement for PSR J0740+6620 and tidal deformability from GW170817 it is necessary to consider a $\mu$-dependent bag pressure that mimics confinement.

18 pages, 7 figures

References in corpus (34)

• GW170817: Observation of Gravitational Waves from a Binary Neutron Star Inspiral
• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• Multi-messenger Observations of a Binary Neutron Star Merger
• GW190814: Gravitational Waves from the Coalescence of a 23 M${}_{\odot }$ Black Hole with a 2.6 M${}_{\odot }$ Compact Object
• PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
• Tidal Love numbers of neutron stars
• A NICER View of the Massive Pulsar PSR J0740+6620 Informed by Radio Timing and XMM-Newton Spectroscopy
• Refined Mass and Geometric Measurements of the High-Mass PSR J0740+6620
• Relativistic theory of tidal Love numbers
• Neutron-star radius constraints from GW170817 and future detections
• Sound velocity bound and neutron stars
• A new quark-hadron hybrid equation of state for astrophysics - I. High-mass twin compact stars
• New Critical Point Induced by the Axial Anomaly in Dense QCD
• Relativistic model for nuclear matter and atomic nuclei with momentum-dependent self-energies
• Modern compact star observations and the quark matter equation of state
• Limiting masses and radii of neutron stars and their implications
• The Green Bank Telescope 350 MHz Drift-scan Survey II: Data Analysis and the Timing of 10 New Pulsars, Including a Relativistic Binary
• A bound on the speed of sound from holography
• Unified Interacting Quark Matter and its Astrophysical Implications
• Equilibrium sequences of non rotating and rapidly rotating crystalline color superconducting hybrid stars
• On covariant nonlocal chiral quark models with separable interactions
• Hybrid stars within a covariant, nonlocal chiral quark model
• Relativistic hybrid stars in light of the NICER PSR J0740+6620 radius measurement
• Two-solar-mass hybrid stars: a two model description with the Nambu-Jona-Lasinio quark model
• Parametrization of a nonlocal, chiral quark model in the instantaneous three-flavor case. Basic formulas and tables
• Running mass, effective energy and confinement: the lattice quark propagator in Coulomb gauge
• Hybrid neutron stars in the mass-radius diagram
• Hybrid neutron stars based on a modified PNJL model
• Pion radiative weak decays in nonlocal chiral quark models
• Neutron stars with crossover to color superconducting quark matter
• Strong-interaction matter under extreme conditions from chiral quark models with nonlocal separable interactions
• Locating the special point of hybrid neutron stars
• Confining density functional approach for color superconducting quark matter and mesonic correlations

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• Speed of Sound in Hybrid Stars and the Role of Bag Pressure in the Emergence of Special Points on M-R Variation of Hybrid Stars
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• XTE J1814-338 as a dark matter admixed neutron star
• Detectability of a phase transition in neutron star matter with third-generation gravitational wave interferometers
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• A Detailed Analysis of the Special Points on $M-R$ Solutions of Hybrid (Twin) Stars
• Pressure and speed of sound in two-flavor color-superconducting quark matter at next-to-leading order
• Thermal twin stars within a hybrid equation of state based on a nonlocal chiral quark model compatible with modern astrophysical observations
• A Bayesian study of quark models in view of recent astrophysical constraints
• Implications of supermassive neutron stars for the form of the equation of state of hybrid stars
• Constraining free parameters of a color superconducting non-local Nambu-Jona-Lasinio model using Bayesian analysis of neutron stars mass and radius measurements
• Radial and Non-Radial Oscillations of Inverted Hybrid Stars
• Hybrid Stars Built with Density Dependent Models
• Hybrid stars with large quark cores within the parity doublet model and modified NJL model
• Cold quark matter in a quasiparticle model: thermodynamic consistency and stellar properties
• Bayesian analysis of hybrid neutron star EOS constraints within an instantaneous nonlocal chiral quark matter model
• Asymptotically conformal CFL quark matter within a nonlocal chiral quark model
• Hadron-quark phase transition in neutron star by combining the relativistic Brueckner-Hartree-Fock theory and Dyson-Schwinger equation approach
• Bayesian Quantification of Observability and Equation of State of Twin Stars
• Effects of phase transition in hybrid stars from quark-meson coupling hadronic matter to deconfined quark matter
• Hybrid isentropic twin stars
• Bayesian Inference of Hybrid Star Properties from Future High-Precision Measurements of Their Radii
• Bayesian inference favors quark matter in neutron star interiors
• Baryon and meson masses in the Nambu--Jona-Lasinio model: A Bayesian approach
• A new class of hybrid EoS with multiple critical endpoints for simulations of supernovae, neutron stars and their mergers
• $f$-mode Oscillations for Hyperons and H-dibaryons in Neutron Stars
• Density functional approach to quark matter with confinement and color superconductivity