Chiral symmetry restoration and the $\Delta$ matter formation in neutron stars

Abstract

We analyze the effects of chiral symmetry restoration in hadronic matter, including the lowest-lying baryonic resonance $\Delta$ based on the parity doublet model. We study the role of $\Delta$ and its chiral partner on the equation of state (EoS) of dense matter under neutron star (NS) conditions of $\beta$-equilibrium and charge neutrality. We find that the softening of the EoS driven by the early onset of $\Delta$ matter due to partial restoration of chiral symmetry allows accommodating the modern multi-messenger astrophysical constraints on the mass, radius, and tidal deformability. The softening above the saturation density is accompanied by subsequent stiffening at high densities. We also find that the matter composition in the NS cores may be different upon variations of the repulsive interactions of $\Delta$ baryons in hadronic matter.

arXiv admin note: text overlap with arXiv:2110.11056, arXiv:2004.09566

References in corpus (22)

• Shapiro delay measurement of a two solar mass neutron star
• A Massive Pulsar in a Compact Relativistic Binary
• 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
• Tidal Love numbers of neutron stars
• Relativistic theory of tidal Love numbers
• Constraints on the high-density nuclear equation of state from the phenomenology of compact stars and heavy-ion collisions
• An effective chiral Hadron-Quark Equation of State
• Cold, dense nuclear matter in a SU(2) parity doublet model
• Critical Density and Impact of $\Delta (1232)$ Resonance Formation in Neutron Stars
• Implications from GW170817 for $\Delta$-isobar admixed hypernuclear compact stars
• Nucleons and parity doubling across the deconfinement transition
• Nuclear Matter and Neutron stars in a Parity Doublet Model
• Neutron stars with small radii -- the role of delta resonances
• Delta baryons and diquark formation in the cores of neutron stars
• An effective model for the QCD phase transitions at finite baryon density
• $\Delta$ (1232) effects in density-dependent relativistic Hartree-Fock theory and neutron stars
• Many-body forces in the equation of state of hyperonic matter
• The application of the Quark-Hadron Chiral Parity-Doublet Model to neutron star matter
• Neutron star mass limit at $2M_{\odot }$ supports the existence of a CEP
• Variation of delta baryon mass and hybrid star properties in static and rotating conditions
• Interplay between chiral dynamics and repulsive interactions