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Related papers: Theta vacuum effects on QCD phase diagram

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We investigate the chiral phase transition in the quark-meson effective model using optimised perturbation theory to one loop. Certain terms in the free energy are frequently omitted in calculations, on the assumption that their…

High Energy Physics - Phenomenology · Physics 2011-07-13 Rashid Khan , Lars T. Kyllingstad

Effects of the vector-type four-quark interaction on QCD phase structure are investigated in the imaginary chemical potential region, by using the Polyakov-loop extended Nambu-Jona-Lasinio (PNJL) model with the extended Z3 symmetry. In the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Yuji Sakai , Kouji Kashiwa , Hiroaki Kouno , Masayuki Matsuzaki , Masanobu Yahiro

Fluctuations in the vicinity of a phase transition are important but neglected in mean-field theory. In order to assess the influence of such fluctuations on the critical endpoint and the size of the critical region in the QCD phase…

High Energy Physics - Phenomenology · Physics 2009-04-14 Bernd-Jochen Schaefer

We explore a phenomenological extension of the Polyakov-Nambu-Jona-Lasinio (PNJL) model by introducing a curvature-sensitive effective contribution to the Polyakov loop potential, motivated by the hypothesis that the non-perturbative QCD…

We study the effects of temporal UV-cutoff on the chiral critical surface in hot and dense QCD using a chiral effective model. Recent lattice QCD simulations indicate that the curvature of the critical surface might change toward the…

High Energy Physics - Phenomenology · Physics 2011-05-19 Jiunn-Wei Chen , Hiroaki Kohyama , Udit Raha

We describe paths in the configuration space of (3+1) dimensional QED whose relative quantum phase (or relative phase in the functional integral) depends on the value of the theta angle. The final configurations on the two paths are related…

High Energy Physics - Theory · Physics 2020-05-18 Stephen D. H. Hsu

We show, in general, that when a discontinuity of either zeroth-order or first-order takes place in an order parameter such as the chiral condensate, discontinuities of the same order emerge in other order parameters such as the Polyakov…

High Energy Physics - Phenomenology · Physics 2009-08-17 Kouji Kashiwa , Yuji Sakai , Hiroaki Kouno , Masayuki Matsuzaki , Masanobu Yahiro

The Quantum Chromodynamics (QCD) phase structure has been studied using the Polyakov-loop augmented quark-meson model (PQM) in the extended mean field approximation (e-MFA) where the quark one-loop vacuum term is included.~When the…

High Energy Physics - Phenomenology · Physics 2023-05-26 Suraj Kumar Rai , Vivek Kumar Tiwari

We extend a previous investigation of the QCD phase diagram with heavy quarks in the context of background field methods by including the two-loop corrections to the background field effective potential. The nonperturbative dynamics in the…

High Energy Physics - Phenomenology · Physics 2018-05-02 J. Maelger , U. Reinosa , J. Serreau

In extensions of the Standard Model with no dimensionful parameters the electroweak phase transition can be delayed to temperatures of order 100 MeV. Then the chiral phase transition of QCD can proceed with 6 massless quarks. The top-quark…

High Energy Physics - Phenomenology · Physics 2021-12-22 Dietrich Bodeker

We investigate the QCD phase diagram of isospin asymmetric matter using the Polyakov loop extended quark meson (PQM) model with vector interaction. The critical point temperature is found to decrease in isospin asymmetric matter and…

Nuclear Theory · Physics 2013-10-30 Hiroshi Ueda , Takashi Z. Nakano , Akira Ohnishi , Marco Ruggieri , Kohsuke Sumiyoshi

We investigate the phase structure of the Nambu--Jona-Lasinio model at zero temperature, allowing for a two-dimensional spatial dependence of the chiral condensate. Applying the mean-field approximation, we consider various periodic…

High Energy Physics - Phenomenology · Physics 2015-06-04 Stefano Carignano , Michael Buballa

We study QCD vacuum structure with the topological $\theta$ angle using a recently proposed semiclassical approach on $\mathbb{R}^2 \times T^2$ with the 't Hooft and baryon magnetic fluxes. Under the assumption of adiabatic continuity in…

High Energy Physics - Theory · Physics 2024-04-24 Yui Hayashi , Yuya Tanizaki

The chiral condensate, which is constant in vacuum, may become spatially modulated at moderately high densities where in the traditional picture of the QCD phase diagram a first-order chiral phase transition occurs. We review the current…

High Energy Physics - Phenomenology · Physics 2015-06-19 Michael Buballa , Stefano Carignano

We discuss the influence of a helicity imbalance on the phase diagram of dense QCD at finite temperature. We argue that the helical chemical potential is a thermodynamically relevant quantity in theories with the mass gap generation. Using…

High Energy Physics - Theory · Physics 2021-05-19 M. N. Chernodub , Victor E. Ambrus

The effect of the isospin/charge asymmetry and an external magnetic field in the location of the critical end point (CEP) in the QCD phase diagram is investigated. By using the 2+1 flavor Nambu--Jona-Lasinio model with Polyakov loop (PNJL),…

High Energy Physics - Phenomenology · Physics 2015-08-10 Pedro Costa , Márcio Ferreira , Constança Providência , Hubert Hansen , Débora P. Menezes

I discuss recent results obtained by our group within the Nambu-Jona Lasinio model with the Polyakov loop. I focus on the two flavor version of the model, discussing the phase diagram in the $\mu-T$ plane in the case in which electrical…

High Energy Physics - Phenomenology · Physics 2009-01-14 M. Ruggieri

The Cornell potential with the best fitted parameters $\alpha_{s}$ and $\kappa$ are modified by adding terms derived from non-perturbative QCD, which are characterized by a series of non-vanishing vacuum condensates of quarks and gluons. In…

High Energy Physics - Phenomenology · Physics 2008-11-26 Y. B. Ding , X. -H. Guo , X. Q. Li , P. N. Shen

We will report recent progress on the QCD phase diagram at finite temperature and density. In particular, we discuss the universal scaling of the chiral transition in the limit of two massless quarks and one strange quark. We also discuss…

High Energy Physics - Lattice · Physics 2025-04-02 Christian Schmidt

The effect of Polyakov loop on the QCD phase diagram at high density is studied within the Nambu-Jona Lasinio model with Polyakov loop (PNJL model). We point out that the color neutrality is missing in the standard PNJL model at finite…

High Energy Physics - Phenomenology · Physics 2009-01-14 H. Abuki