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Related papers: QCD at Large $\theta$ Angle and Axion Cosmology

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We investigate the QCD chiral phase transition at finite chemical potential $\mu$, using the renormalization group (RG) to characterize the infrared behavior of sigma models constrained by the flavor and spacetime symmetries. The results…

High Energy Physics - Phenomenology · Physics 2009-10-31 Stephen D. H. Hsu , Myckola Schwetz

We unveil the impact of the $\theta$-angle on the QCD phase diagram at nonzero isospin and strangeness chemical potentials for three light flavors and different quark mass ratios. We establish the phase boundaries as well as the nature of…

High Energy Physics - Phenomenology · Physics 2025-01-09 Jahmall Bersini , Alessandra D'Alise , Clelia Gambardella , Francesco Sannino

We discuss how the inclusion of singular gauge fields in the partition function for QCD can lead to a domain-like picture for the QCD vacuum by virtue of specific conditions on quantum fluctuations at the singularities. With a simplified…

High Energy Physics - Phenomenology · Physics 2017-08-23 A. C. Kalloniatis , S. N. Nedelko

We investigate the phase transition in full QCD with two flavors of staggered fermions in presence of a constant abelian chromomagnetic field. We find that the critical temperature depends on the strength of the chromomagnetic field and…

High Energy Physics - Lattice · Physics 2008-11-26 Paolo Cea , Leonardo Cosmai , Massimo D'Elia

While chiral symmetry breaking in the QCD vacuum is attributed to nonzero chiral condensate, an alternative symmetry breaking pattern with no chiral condensate is also possible, as pointed out by Stern. This hypothetical phase was excluded…

High Energy Physics - Phenomenology · Physics 2015-10-06 Takuya Kanazawa

We investigate the dependence of the QCD vacuum structure on the $\theta$-angle and quark mass, using the Di-Vecchia--Veneziano model. Although the Di-Vecchia--Veneziano model is a chiral effective model, it contains the topological…

High Energy Physics - Phenomenology · Physics 2015-09-23 Kazuya Mameda

Heavy-ion collisions performed in the beam energy range accessible by the NICA collider facility are expected to produce systems of extreme net-baryon densities and can thus reach yet unexplored regions of the QCD phase diagram. Here, one…

Nuclear Theory · Physics 2016-09-21 Marlene Nahrgang , Christoph Herold

We investigate the deconfining phase transition in SU(3) pure gauge theory and in full QCD with two flavors of staggered fermions. The phase transition is detected by measuring the free energy in presence of an abelian monopole background…

High Energy Physics - Lattice · Physics 2009-11-10 Paolo Cea , Leonardo Cosmai , Massimo D'Elia

Recent experiments in heavy ion collisions have shown the possibility of creating parity-odd domains resulting from the $\theta$ term in strong interaction Lagrangian. The $\theta$ term originates from the nontrivial solution of QCD vacuum…

Nuclear Theory · Physics 2015-06-16 Eun-Joo Kim , Jong Bum Choi

We study the thermal transition of QCD with two degenerate light flavours by lattice simulations using $O(a)$-improved Wilson quarks. Temperature scans are performed at a fixed value of $N_t = (aT)^{-1}=16$, where $a$ is the lattice spacing…

High Energy Physics - Lattice · Physics 2017-02-23 Bastian B. Brandt , Anthony Francis , Harvey B. Meyer , Owe Philipsen , Daniel Robaina , Hartmut Wittig

We study the qualitative features of the QCD phase diagram in the context of the linear quark-meson model with two flavours, using the exact renormalization group. We identify the universality classes of the second-order phase transitions…

High Energy Physics - Theory · Physics 2010-04-05 N. Tetradis

We investigate the combined effects of rotation and finite quark chemical potential on inhomogeneous chiral condensation and the chiral phase diagram within the soft-wall holographic QCD model. Using the five-dimensional AdS-RN metric, we…

High Energy Physics - Phenomenology · Physics 2026-04-14 D. -Y. Long , S. -Q. Feng

The QCD phase transition is studied on $16^3$ and $32^3 \times 4$ lattices both with and without quark loops. We introduce a new zero-flavor or quenched species of quark $\zeta$ and study the resulting chiral condensate, $\azbz$ as a…

High Energy Physics - Lattice · Physics 2009-10-28 Shailesh Chandrasekharan , Norman Christ

The QCD axial anomaly, by coupling the chiral condensate and BCS pairing fields of quarks in dense matter, leads to a new critical point in the QCD phase diagram \cite{HTYB,chiral2}, which at sufficiently low temperature should terminate…

Nuclear Theory · Physics 2008-11-26 Gordon Baym , Tetsuo Hatsuda , Motoi Tachibana , Naoki Yamamoto

It follows on general grounds that the theta dependence in QCD is more complicated than suggested by the large N_c approach or instanton arguments. Generically, the vacuum energy E_{vac}(\theta) is a multi-valued function of \theta…

High Energy Physics - Phenomenology · Physics 2011-04-20 Igor Halperin , Ariel Zhitnitsky

We explore the possibility that QCD may undergo a phase transition as a function of the strange quark mass. This would hint towards models with ``spontaneous color symmetry breaking'' in the vacuum. For two light quark flavors we classify…

High Energy Physics - Phenomenology · Physics 2016-09-06 C. Wetterich

We propose a method to probe the nature of phase transitions in lattice QCD at finite temperature and density, which is based on the investigation of an effective potential as a function of the average plaquette. We analyze data obtained in…

High Energy Physics - Lattice · Physics 2008-11-26 Shinji Ejiri

We study the color-flavor locked phase of QCD with three massless quarks at high chemical potential and small non zero temperatures. We make use of the recently introduced effective action to describe such a phase. We obtain the exact order…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Casalbuoni , R. Gatto

We show on the basis of an effective theory of QCD that a wide variety of observables in the hadron world is governed by the chiral symmetry together with an interplay between the axial anomaly and the explicit symmetry breaking due to the…

High Energy Physics - Phenomenology · Physics 2016-11-03 Teiji Kunihiro

We study the impact of axial-anomaly effects on the chiral phase structure in a $U(3)$-extended soft-wall holographic QCD model. Including the pseudoscalar singlet sector allows for a dynamical description of the $\eta$-$\eta^\prime$ system…

High Energy Physics - Phenomenology · Physics 2026-03-16 Xin-Yi Liu , Yue-Liang Wu , Zhen Fang
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