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Related papers: Eight-quark interactions as a chiral thermometer

200 papers

The temperature behaviour of meson condensates $<\sigma_0>$ and $<\sigma_8>$ is calculated in the $SU(3)\times SU(3)$-linear sigma model. The couplings of the Lagrangian are fitted to the physical $\pi,K,\eta,\eta'$ masses, the pion decay…

High Energy Physics - Phenomenology · Physics 2010-11-01 D. Metzger , H. Meyer--Ortmanns , H. --J. Pirner

We review the Nambu-Jona-Lasinio (NJL) approach to the dynamical breaking of chiral symmetry in Quantum Chromodynamics (QCD). The subjects treated in Part I include the vacuum structure of QCD, mass spectra and coupling constants of…

High Energy Physics - Phenomenology · Physics 2010-11-01 T. Hatsuda , T. Kunihiro

We extend the modified Nambu-Jona-Lasinio (NJL) model -- incorporating exchange interactions via the Fierz transformation -- to finite temperatures in both two- and three-flavor scenarios, and investigate the properties of protoquark stars…

High Energy Physics - Phenomenology · Physics 2026-02-18 Wen-Li Yuan , Nobutoshi Yasutake , Renxin Xu

We have simulated lattice QCD with 2 flavours of massless staggered quarks. An irrelevant chiral 4-fermion interaction was added to the standard quark action to allow us to simulate at zero quark mass. Thermodynamics was studied on lattices…

High Energy Physics - Lattice · Physics 2009-11-07 J. B. Kogut , D. K. Sinclair

Lattice QCD with additional chiral-invariant four-fermion interactions is studied at nonzero temperature. Staggered Kogut-Susskind quarks are used. The four-fermion interactions are implemented by introducing bosonic auxiliary fields. A…

High Energy Physics - Lattice · Physics 2009-10-31 Michael Chavel

We present some results pertaining quantities which are regarded as good indicators of the pseudo-critical temperatures for the deconfinement and partial chiral restoration transitions using a polynomial form for the Polyakov potential part…

High Energy Physics - Phenomenology · Physics 2013-02-07 João Moreira , Brigitte Hiller , Alexander Osipov , Alex Blin

In this work, expanding on previous analyses, we employ an effective Lagrangian approach to investigate the mass spectrum of scalar and pseudoscalar mesons at finite temperature, above the (pseudo-)critical temperature $T_c$, in a…

High Energy Physics - Phenomenology · Physics 2026-05-21 Giulio Cianti , Enrico Meggiolaro

Low energy hadron phenomenology involving the (u,d,s) quarks is often approached through effective multi-quark Lagrangians with the symmetries of QCD. A very successful approach consists in taking the four-quark Nambu--Jona-Lasinio…

High Energy Physics - Phenomenology · Physics 2008-12-19 Brigitte Hiller , Alexander A. Osipov , Veronique Bernard , Alex H. Blin

We extend our previous study of the quark-hadron phase transition at finite temperatures with zero net baryon density by two flavor Nambu-Jona-Lasinio model with Polyakov loop to the three flavor case in a scheme which incorporates flavor…

High Energy Physics - Phenomenology · Physics 2015-07-01 Kanako Yamazaki , T. Matsui

We investigate the effect of screening of the four-quarks contact interactions by the ring diagram at finite temperature and density in an effective chiral model inspired by QCD in the Coulomb gauge. As a consequence, a medium-dependent…

High Energy Physics - Phenomenology · Physics 2023-09-07 Michał Szymański , Pok Man Lo , Krzysztof Redlich , Chihiro Sasaki

We simulate lattice QCD with an irrelevant chiral 4-fermion interaction which allows us to simulate at zero quark mass. This enables us to study the finite-temperature chiral-symmetry-restoring phase transition for 2 massless quark…

High Energy Physics - Lattice · Physics 2007-05-23 J. B. Kogut , D. K. Sinclair

We study, in the PNJL model, how the entropy of interacting quarks reflects the change in the effective degrees of freedom as the temperature increases through the quark-hadron phase transition. With inclusion of mesonic correlations, the…

High Energy Physics - Phenomenology · Physics 2015-06-22 Kanako Yamazaki , T. Matsui , Gordon Baym

It is shown that the strange quark mass undergoes a first order transition in a generalized 3 flavor Nambu--Jona-Lasinio (NJL) Lagrangian which includes a complete set of explicit chiral symmetry breaking interactions. This transition…

High Energy Physics - Phenomenology · Physics 2014-11-13 J. Morais , J. Moreira , B. Hiller , A. H. Blin , A. A. Osipov

We study the finite temperature phase transition of lattice QCD with an irrelevant chiral 4-fermion interaction and two massless quark flavours, on $8^3 \times 4$ and $12^2 \times 24 \times 4$ lattices. The strength of the 4-fermion…

High Energy Physics - Lattice · Physics 2007-05-23 J. B. Kogut , D. K. Sinclair

The quark-hadron phase transition at finite temperature and baryon chemical potential is investigated in an extended NJL model with scalar-vector eight-point interaction by comparing the pressure of symmetric nuclear matter with that of the…

High Energy Physics - Phenomenology · Physics 2016-06-21 T. -G. Lee , Y. Tsue , J. da Providencia , C. Providencia , M. Yamamura

The flavor-dependent quark-antiquark contact interactions, induced by vacuum polarization and recently derived for flavor U(3) Nambu-Jona-Lasinio model, are articulated with the resulting mixing effects emerging from flavor symmetry…

High Energy Physics - Phenomenology · Physics 2025-08-11 F. L. Braghin

In this study, we investigate the mass spectrum of $\pi$ and $\sigma$ mesons at finite chemical potential using the self-consistent NJL model and the Fierz-transformed interaction Lagrangian. The model introduces an arbitrary parameter…

High Energy Physics - Phenomenology · Physics 2023-10-09 Xiaozhu Yu , Xinyang Wang

We review the effect on vacuum properties and magnetic catalysis, of adding the most general 0-spin 8-quark (8q) interactions to the combined SU(3) flavor Nambu--Jona-Lasinio (NJL) and 6-quark (6q) 't Hooft interaction Lagrangian.

High Energy Physics - Phenomenology · Physics 2012-04-24 B. Hiller , A. A. Osipov , A. H. Blin , J. Providencia

We present our lattice studies of SU(3) gauge theory with $N_f$ = 8 degenerate fermions in the fundamental representation. Using nHYP-smeared staggered fermions we study finite-temperature transitions on lattice volumes as large as $L^3…

The six-quark instanton induced 't Hooft interaction is considered in combination with the Nambu-Jona-Lasinio (NJL) type U_L(3)X U_R(3) chiral symmetric Lagrangian. We discuss the bosonization of this multi-quark interaction, taking the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Brigitte Hiller , Alexander A. Osipov , Alex H. Blin