Mean-field approximation for the chiral soliton in a chiral phase transition

The thermodynamics of a first-order chiral phase transition is considered in the presence of spinodal phase separation using the Nambu-Jona-Lasinio model in the mean field approximation. We focus on the behavior of conserved charge fluctuations. We show that in non-equilibrium the specific heat and charge susceptibilities diverge as the system crosses the isothermal spinodal lines.

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QCD susceptibilities in the presence of the chiral chemical potential

Modern Physics Letters A ◽

10.1142/s0217732320501370 ◽

2020 ◽

Vol 35 (16) ◽

pp. 2050137

Author(s):

Run-Lin Liu ◽

Hong-Shi Zong

Keyword(s):

Phase Transition ◽

Phase Diagram ◽

Chemical Potential ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Chiral Phase ◽

First Order Phase Transition ◽

Phase Transition Region ◽

First Order Phase

In this paper, chiral chemical potential [Formula: see text] is introduced to investigate the QCD susceptibilities and chiral phase transition within the Polyakov-loop-extended Nambu–Jona-Lasinio models in the mean-field approximation. We concentrate on the effect of chiral chemical potential on the phase diagram and the QCD susceptibilities. Moreover, it is worth noting that chiral chemical potential has more and more prominent impact on the susceptibilities and the phase diagram with the decrease of temperature based on our results, which coincides with the prediction that the chiral symmetry is dynamically broken in the first-order phase transition region and gets partly restored in the crossover region.

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SU(3) Polyakov linear-sigma model: Conductivity and viscous properties of QCD matter in thermal medium

International Journal of Modern Physics A ◽

10.1142/s0217751x1650175x ◽

2016 ◽

Vol 31 (34) ◽

pp. 1650175 ◽

Cited By ~ 16

Author(s):

Abdel Nasser Tawfik ◽

Abdel Magied Diab ◽

M. T. Hussein

Keyword(s):

Lattice Qcd ◽

Mean Field ◽

Field Approximation ◽

Linear Sigma Model ◽

Dense Medium ◽

Mean Field Approximation ◽

Chiral Phase ◽

Strange Quarks ◽

Transition Formula ◽

Thermal Medium

In mean field approximation, the grand canonical potential of SU(3) Polyakov linear-[Formula: see text] model (PLSM) is analyzed for chiral phase transition, [Formula: see text] and [Formula: see text] and for deconfinement order-parameters, [Formula: see text] and [Formula: see text] of light- and strange-quarks, respectively. Various PLSM parameters are determined from the assumption of global minimization of the real part of the potential. Then, we have calculated the subtracted condensates [Formula: see text]. All these results are compared with recent lattice QCD simulations. Accordingly, essential PLSM parameters are determined. The modeling of the relaxation time is utilized in estimating the conductivity properties of the QCD matter in thermal medium, namely electric [Formula: see text] and heat [Formula: see text] conductivities. We found that the PLSM results on the electric conductivity and on the specific heat agree well with the available lattice QCD calculations. Also, we have calculated bulk and shear viscosities normalized to the thermal entropy, [Formula: see text] and [Formula: see text], respectively, and compared them with recent lattice QCD. Predictions for [Formula: see text] and [Formula: see text] are introduced. We conclude that our results on various transport properties show some essential ingredients, that these properties likely come up with, in studying QCD matter in thermal and dense medium.

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GROSS–WITTEN POINT AND DECONFINEMENT

International Journal of Modern Physics A ◽

10.1142/s0217751x05028089 ◽

2005 ◽

Vol 20 (19) ◽

pp. 4469-4474 ◽

Cited By ~ 1

Author(s):

ROBERT D. PISARSKI

Keyword(s):

Phase Transition ◽

Gauge Theory ◽

Critical Point ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

First Order

Following Aharony et al., we analyze the deconfining phase transition in a SU(∞) gauge theory in mean field approximation. The Gross–Witten model emerges as an "ultra"-critical point for deconfinement: while thermodynamically of first order, masses vanish, asymmetrically, at the transition. Potentials for N = 3 are also shown.

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Hybrid Stars in the Framework of NJL Models

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194517600266 ◽

2017 ◽

Vol 45 ◽

pp. 1760026 ◽

Cited By ~ 2

Author(s):

Gustavo A. Contrera ◽

Milva Orsaria ◽

I. F. Ranea-Sandoval ◽

Fridolin Weber

Keyword(s):

Phase Transition ◽

Quark Matter ◽

Mean Field ◽

Field Approximation ◽

Hadronic Matter ◽

High Mass ◽

Mean Field Approximation ◽

Soft Phase ◽

Non Local ◽

Hybrid Stars

We compute models for the equation of state (EoS) of the matter in the cores of hybrid stars. Hadronic matter is treated in the non-linear relativistic mean-field approximation, and quark matter is modeled by three-flavor local and non-local Nambu−Jona-Lasinio (NJL) models with repulsive vector interactions. The transition from hadronic to quark matter is constructed by considering either a soft phase transition (Gibbs construction) or a sharp phase transition (Maxwell construction). We find that high-mass neutron stars with masses up to [Formula: see text] may contain a mixed phase with hadrons and quarks in their cores, if global charge conservation is imposed via the Gibbs conditions. However, if the Maxwell conditions is considered, the appearance of a pure quark matter core either destabilizes the star immediately (commonly for non-local NJL models) or leads to a very short hybrid star branch in the mass-radius relation (generally for local NJL models).

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First Principles Study of the Phase Transitions of MnAs

MRS Proceedings ◽

10.1557/proc-0941-q08-17 ◽

2006 ◽

Vol 941 ◽

Author(s):

Ivan Rungger ◽

Stefano Sanvito

Keyword(s):

Phase Transition ◽

Curie Temperature ◽

Cell Volume ◽

Order Phase Transition ◽

Structural Changes ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

First Order Phase Transition ◽

The Stability

ABSTRACTThe magnetic and structural properties of MnAs are investigated by mapping ab initio total energies onto a Heisenberg Hamiltonian. We study the dependence of the Curie temperature over the unit cell volume and an orthorhombic distortion by using the mean field approximation, and find that for orthorhombically distorted cells the Curie temperature is much smaller than for hexagonal cells. We provide an explanation for the structural changes of both the first order phase transition at 318 K and the second order phase transition at 400 K, with the cell volume driving the stability of the different structures in the paramagnetic state. The stable cell is found to be orthorhombic up to a critical lattice constant of about 3.7 Å, above which it remains hexagonal.

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On the stability of two-flavor and three-flavor quark matter in quark stars within the framework of NJL model

Modern Physics Letters A ◽

10.1142/s0217732320503216 ◽

2020 ◽

Vol 35 (39) ◽

pp. 2050321 ◽

Cited By ~ 1

Author(s):

Qianyi Wang ◽

Tong Zhao ◽

Hongshi Zong

Keyword(s):

Quark Matter ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Chiral Phase ◽

Quark Stars ◽

Njl Model ◽

The Stability ◽

Chiral Susceptibility ◽

Strong Interaction Matter

Following our recently proposed self-consistent mean field approximation approach, we have done some researches on the chiral phase transition of strong interaction matter within the framework of Nambu-Jona-Lasinio (NJL) model. The chiral susceptibility and equation of state (EOS) are computed in this work for both two-flavor and three-flavor quark matter for contrast. The Pauli–Villars scheme, which can preserve gauge invariance, is used in this paper. Moreover, whether the three-flavor quark matter is more stable than the two-flavor quark matter or not in quark stars is discussed in this work. In our model, when the bag constant are the same, the two-flavor quark matter has a higher pressure than the three-flavor quark matter, which is different from what Witten proposed in his pioneering work.

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Exotic Baryons in Chiral Soliton Models

Universe ◽

10.3390/universe4120142 ◽

2018 ◽

Vol 4 (12) ◽

pp. 142

Author(s):

Herbert Weigel

Keyword(s):

Canonical Quantization ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Collective Coordinates ◽

Zero Modes ◽

Chiral Soliton ◽

Exotic Baryons ◽

The Mean

We cautiously review the treatment of pentaquark exotic baryons in chiral soliton models. We consider two examples and argue that any consistent and self-contained description must go beyond the mean field approximation that only considers the classical soliton and the canonical quantization of its (would-be) zero modes via collective coordinates.

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The behaviors of the solutions of the quark gap equation in the NJL model with the self-consistent mean field approximation

Modern Physics Letters A ◽

10.1142/s021773232150245x ◽

2021 ◽

Author(s):

Zu-Qing Wu ◽

Jia-Lun Ping ◽

Hong-Shi Zong

Keyword(s):

Chiral Limit ◽

Mean Field ◽

Stable Solution ◽

Field Approximation ◽

The Self ◽

Mean Field Approximation ◽

Chiral Phase ◽

Gap Equation ◽

Self Consistent ◽

Exchange Channel

In this paper, we use the self-consistent mean field approximation to study the Quantum Chromodynamics (QCD) phase transition. In the self-consistent mean field approximation of the Nambu–Jona-Lasinio (NJL) model, a parameter [Formula: see text] is introduced, which reflects the weight of “direct” channel and the “exchange” channel and needs to be determined by experiments (as mentioned in a recent work [T. Zhao, W. Zheng, F. Wang, C.-M. Li, Y. Yan, Y.-F. Huang and H.-S. Zong, Phys. Rev. D 100, 043018 (2019)], the results with [Formula: see text] are in good agreement with astronomical observation data on the latest binary neutron star merging. This indicates that the contribution of “exchange” channel should be considered, and [Formula: see text] is a possible choice). By comparing the results with different parameter [Formula: see text]’s ([Formula: see text], [Formula: see text] and [Formula: see text]), we study the influence of “exchange” channel on the behavior of the solutions of the quark gap equation and the critical point of chiral phase transition. Our results show that the second-order chiral phase turns to the crossover from the chiral limit to the non-chiral limit around [Formula: see text] in the case of [Formula: see text]. The difference of the quark mass with different [Formula: see text]’s mainly occurs in the intermediate temperatures for the different fixed chemical potentials. At zero temperature and the chemical potential [Formula: see text] there will be two solutions (including a meta-stable solution) of gap equation with [Formula: see text], and as [Formula: see text] increases it will be only one solution left (the meta-stable solution will disappear until [Formula: see text]). Besides, the discrepancy of the critical temperature (above which the pseudo-Wigner solution and negative Nambu solution will disappear) in the three cases of [Formula: see text] will become large when the chemical potential increases.

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