Half-Skyrmions and the Equation of State for Compact-Star Matter

Abstract

The half-skyrmions that appear in dense baryonic matter when skyrmions are put on crystals modify drastically hadron properties in dense medium and affect strongly the nuclear tensor forces, thereby influencing the equation of state (EoS) of dense nuclear and asymmetric nuclear matter. The matter comprised of half skyrmions has vanishing quark condensate but non-vanishing pion decay constant and could be interpreted as a hadronic dual of strong-coupled quark matter. We infer from this observation combined with certain predictions of hidden local symmetry in low-energy hadronic interactionsa a set of new scaling laws -- called "new-BR" -- for the parameters in nuclear effective field theory controlled by renormalization-group flow. They are subjected to the EoS of symmetric and asymmetric nuclear matter, and are then applied to nuclear symmetry energies and properties of compact stars. The changeover from the skyrmion matter to a half-skyrmion matter that takes place after the cross-over density $n_{1/2}$ provides a simple and natural field theoretic explanation for the change of the EoS from soft to stiff at a density above that of nuclear matter required for compact stars as massive as $\sim 2.4M_{\odot }$. Cross-over density in the range $1.5n_0 \lsim n_{1/2} \lsim 2.0 n_0$ has been employed, and the possible skyrmion half-skyrmion coexistence {or cross-over} near $n_{1/2}$ is discussed. The novel structure of {the tensor forces and} the EoS obtained with the new-BR scaling is relevant for neutron-rich nuclei and compact star matter and could be studied in RIB (rare isotope beam) machines.

12 pages, 7 figures, slightly revised for PRC, in press

References in corpus (11)

• Shapiro delay measurement of a two solar mass neutron star
• "Deconfined" quantum critical points
• Hadron-Quark Crossover and Massive Hybrid Stars with Strangeness
• Chiral three-nucleon interaction and the carbon-14 dating beta decay
• Half-Skyrmions, Tensor Forces and Symmetry Energy in Cold Dense Matter
• Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions
• Dense Baryonic Matter in Hidden Local Symmetry Approach: Half-Skyrmions and Nucleon Mass
• Pions in Large-$N$ Quantum Chromodynamics
• Low-momentum interactions with Brown-Rho-Ericson scalings and the density dependence of the nuclear symmetry energy
• Low-momentum ring diagrams of neutron matter at and near the unitary limit
• Proton Mass, Topology Change and Tensor Forces in Compressed Baryonic Matter

Cited by in corpus (26)

• Charged anisotropic models for quark stars
• Asymmetric nuclear matter in a parity doublet model with hidden local symmetry
• Scale-Invariant Hidden Local Symmetry, Topology Change and Dense Baryonic Matter II
• Interplay between ω-Nucleon Interaction and Nucleon Mass in Dense Baryonic Matter
• Dense Baryonic Matter in Hidden Local Symmetry Approach: Half-Skyrmions and Nucleon Mass
• Dense baryonic matter in conformally-compensated hidden local symmetry: Vector manifestation and chiral symmetry restoration
• Skyrmions with vector mesons in the hidden local symmetry approach
• Scale-Invariant Hidden Local Symmetry, Topology Change and Dense Baryonic Matter
• Baryon chemical potential and in-medium properties of BPS skyrmions
• Topology and emergent symmetries in dense compact star matter
• Magnetic response of baryon properties in a skyrmion model
• Topology Change and Tensor Forces for the EoS of Dense Baryonic Matter
• Neutron stars within the Skyrme model
• Introduction to low-momentum effective interactions with Brown-Rho scaling and three-nucleon forces
• Generalized skyrmion crystals with applications to neutron stars
• Kaon Condensation in Baryonic Fermi Liquid at High Density
• The Non-Quenching of $g_A$ in Nuclei and Emergent Scale Symmetry in Dense Baryonic Matter
• Fractionized Skyrmions in Dense Compact-Star Matter
• A New Topological "Twist" to BR Scaling
• Compact Star Matter: EoS with New Scaling Law
• Proton Mass, Topology Change and Tensor Forces in Compressed Baryonic Matter
• The "Folk Theorem" on Effective Field Theory: How Does It Fare in Nuclear Physics?
• Partial restoration of chiral symmetry in hot and dense neutron matter
• "Mass Without Mass" and Nuclear Matter
• Dilatons in Dense Baryonic Matter
• Nucleon-anti-nucleon intruder state of Dirac equation for nucleon in deep scalar potential well