Average speed of sound in neutron stars
arXiv:2407.15486 · doi:10.1103/PhysRevC.110.045811
Abstract
The structure of the dense-matter equation of state is essential for the phenomenology of neutron stars. In this work, I relate the thermodynamic properties to the average speed of sound in the interior of a star. I study the consequences of the vanishing of the trace anomaly. In particular, I show that if the trace anomaly vanishes in the centers of maximally massive neutron stars, the speed of sound likely exceeds its conformal value and exhibits nonmonotonic behavior. I also find that the additional assumption of positive definiteness of the trace anomaly naturally induces a local peak of the speed of sound at densities realized in the cores of neutron stars. I also reanalyze the stability condition for hybrid neutron stars. Possible implications for the dense matter equation of state and the phenomenology of neutron stars are also discussed.
arXiv commentmatches published version
References in corpus (63)
- GW170817: Measurements of Neutron Star Radii and Equation of State
- PSR J0030+0451 Mass and Radius from NICER Data and Implications for the Properties of Neutron Star Matter
- A NICER View of PSR J0030+0451: Millisecond Pulsar Parameter Estimation
- Relativistic Shapiro delay measurements of an extremely massive millisecond pulsar
- A New Parameterization for the Lagrangian Density of Relativistic Mean Field Theory
- NJL-model analysis of dense quark matter
- Properties of the binary neutron star merger GW170817
- A NICER View of the Massive Pulsar PSR J0740+6620 Informed by Radio Timing and XMM-Newton Spectroscopy
- The equation of state in (2+1)-flavor QCD
- Gravitational-wave constraints on the neutron-star-matter Equation of State
- Refined Mass and Geometric Measurements of the High-Mass PSR J0740+6620
- Recent Progress in Quantum Hadrodynamics
- Equation of state and neutron star properties constrained by nuclear physics and observation
- Phases of Dense Quarks at Large N_c
- Evidence for quark-matter cores in massive neutron stars
- PSR J0952-0607: The Fastest and Heaviest Known Galactic Neutron Star
- Cold Quark Matter
- Generic conditions for stable hybrid stars
- Constraining the speed of sound inside neutron stars with chiral effective field theory interactions and observations
- Approximate Universal Relations for Neutron Stars and Quark Stars
- Chiral interactions up to next-to-next-to-next-to-leading order and nuclear saturation
- Quarkyonic Matter and Neutron Stars
- How well do we know the neutron-matter equation of state at the densities inside neutron stars? A Bayesian approach with correlated uncertainties
- Interacting quark matter equation of state for compact stars
- On the Sound Speed in Neutron Stars
- Compact stars with sequential QCD phase transitions
- Limiting masses and radii of neutron stars and their implications
- NNNLO pressure of cold quark matter: leading logarithm
- Strongly interacting matter exhibits deconfined behavior in massive neutron stars
- Trace anomaly as signature of conformality in neutron stars
- Tidal deformability with sharp phase transitions in (binary) neutron stars
- Quantifying uncertainties and correlations in the nuclear-matter equation of state
- Third family of compact stars within a nonlocal chiral quark model equation of state
- Mapping neutron star data to the equation of state using the deep neural network
- Cool quark matter
- Dynamical Derivation of the Momentum Space Shell Structure for Quarkyonic Matter
- Reaching percolation and conformal limits in neutron stars
- Nuclear equation of state for arbitrary proton fraction and temperature based on chiral effective field theory and a Gaussian process emulator
- Studying strong phase transitions in neutron stars with gravitational waves
- The Quarkyonic Star
- Evidence against a strong first-order phase transition in neutron star cores: impact of new data
- Inference of the sound speed and related properties of neutron stars
- Equation of state and speed of sound of isospin-asymmetric QCD on the lattice
- A general, scale-independent description of the sound speed in neutron stars
- Stiffening of matter in quark-hadron continuity
- Impact of large-mass constraints on the properties of neutron stars
- What neutron stars tell about the hadron-quark phase transition: a Bayesian study
- Large Sound Speed in Dense Matter and the Deformability of Neutron Stars
- The slope, the hill, the drop, and the swoosh: Learning about the nuclear matter equation of state from the binary Love relations
- Equation of State of Cold Quark Matter to
- Classifications of Twin Star Solutions for a Constant Speed of Sound Parameterized Equation of State
- Holographic quarkyonic matter
- Peaks of sound velocity in two color dense QCD: quark saturation effects and semishort range correlations
- Unified neutron star EOSs and neutron star structures in RMF models
- Trace of the energy-momentum tensor and macroscopic properties of neutron stars
- A field theoretical model for quarkyonic matter
- Cool quark matter with perturbative quark masses
- Unified nuclear matter EOSs constrained by the in-medium balance in density-dependent covariant density functionals
- Neutron star properties with careful parameterization in the (axial)vector meson extended linear sigma model
- Curvature of the energy per particle in neutron stars
- I-Love-: Approximately universal relations for the average neutron star stiffness
- Might Normal Nuclear Matter be Quarkyonic?
- Speed of sound and polytropic index in QCD matter
Cited by in corpus (7)
- How the QCD trace anomaly behaves at the core of twin stars?
- Novel Scalings of Neutron Star Properties from Analyzing Dimensionless Tolman--Oppenheimer--Volkoff Equations
- Properties of the Object HESS J1731-347 as a Twin Compact Star
- Application of Kaluza-Klein Theory in Modeling Compact Stars: Exploring Extra Dimensions
- String-based model with Hagedorn temperature of MeV describes the spectrum of mesons and glueballs
- Is The Trace Anomaly at its Minimum Value at Neutron Star Centers?
- Bayesian Constraints on the Neutron Star Equation of State with a Smooth Hadron-Quark Crossover