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

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This paper investigates the impact of strangeness chemical potential and finite volume on QCD critical end point by employing a (2+1) flavored Polyakov quark meson model. Within the mean-field approximation, the model has been extended to…

Nuclear Theory · Physics 2023-10-09 Nisha Chahal , Suneel Dutt , Arvind Kumar

The complex field $\Phi$ containing the QCD axion has a natural portal coupling to the Higgs doublet of the form $\lambda_{h \phi}|\Phi|^2 |H|^2$. Here we consider the possibility that $\lambda_{h \phi}$ has a natural magnitude for a…

High Energy Physics - Phenomenology · Physics 2017-05-05 J. McDonald

We present the status of our analysis on the order of the finite temperature transition in QCD with two flavors of degenerate fermions. Our new simulations on large lattices support the hypothesis of the first order nature of the…

High Energy Physics - Lattice · Physics 2009-04-14 C. Bonati , G. Cossu , M. D'Elia , A. Di Giacomo , C. Pica

The $U(1)_A$ symmetry of the massless QCD Lagrangian is explicitly broken by the axial anomaly, but it may be effectively restored at finite temperature. Determining the temperature at which this occurs is important for understanding the…

High Energy Physics - Lattice · Physics 2026-04-15 Gert Aarts , Chris Allton , Ryan Bignell , Benjamin Jäger , Seyong Kim , Jon-Ivar Skullerud , Antonio Smecca

The QCD axion is a well-motivated hypothetical particle beyond the Standard Model (SM) and a compelling dark matter candidate. Its relic abundance is highly sensitive to the thermal history of the universe when the temperature is around the…

High Energy Physics - Phenomenology · Physics 2025-06-26 Kun-Feng Lyu , Yue Zhao

I report on the current status of QCD phase diagram at vanishing baryon density. I focus on the QCD phase diagram with three degenerate quark flavor using Highly Improved Staggered Quarks on $N_{\tau}=6$ lattices. No evidence of a first…

High Energy Physics - Lattice · Physics 2015-06-15 Heng-Tong Ding

We map out the QCD phase structure at finite temperature and chemical potential for 2-flavour and 2 + 1-flavour QCD. This is done within a generalised functional approach to QCD put forward in arXiv:2002.07500 [hep-ph]. Specifically we…

High Energy Physics - Phenomenology · Physics 2021-08-18 Fei Gao , Jan M. Pawlowski

We report results of simulations of strong coupling, finite density QCD obtained within a MFA inspired approach where the fermion determinant in the integration measure is replaced by its absolute value. Contrary to the standard wisdom, we…

High Energy Physics - Lattice · Physics 2009-10-31 R. Aloisio , V. Azcoiti , G. Di Carlo , A. Galante , A. F. Grillo

We study one-flavor QCD at finite temperature and chemical potential using the functional renormalization group. We discuss the chiral phase transition in QCD and its order with its underlying mechanism in terms of quarks and gluons and…

High Energy Physics - Phenomenology · Physics 2009-11-10 Jens Braun

We summarize main points of our recent work where we studied the pion condensation for non-zero isospin chemical potential within a holographic QCD model. We confirmed that the second order phase transition with the mean field exponent…

High Energy Physics - Phenomenology · Physics 2014-04-14 Hiroki Nishihara , Masayasu Harada

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

We study QCD with two Dirac fermions in the adjoint representation at finite temperature by Monte Carlo simulations.In such a theory the deconfinement and chiral phase transitions occur at different temperatures. We locate the second order…

High Energy Physics - Lattice · Physics 2009-11-11 J. Engels , S. Holtmann , T. Schulze

In the model of a first order quark-gluon/hadron phase transition in which the hadronic phase is considered as vacuum bubbles growing in the quark-gluon background with chiral symmetry broken inside the bubble, we find the estimate for the…

High Energy Physics - Phenomenology · Physics 2009-10-28 L. Burakovsky

The properties of the QCD partition function at finite chemical potential are studied within the instanton liquid model. It is shown that the density dependence of the quark-induced instanton-antiinstanton (I-A) interaction leads to the…

High Energy Physics - Phenomenology · Physics 2009-10-31 R. Rapp

The scenario that some first-order phase transitions may have taken place in the early Universe offers us one of the most intriguing and fascinating questions in cosmology. Indeed, the role played by the latent "heat" or energy released in…

High Energy Physics - Phenomenology · Physics 2009-11-13 W-Y. P. Hwang

We construct an effective model for the QCD equation of state, taking into account chiral symmetry restoration as well as the deconfinement phase transition. The correct asymptotic degrees of freedom at the high and low temperature limits…

High Energy Physics - Phenomenology · Physics 2011-01-28 J. Steinheimer , S. Schramm , H. Stöcker

In the $\epsilon$-domain of QCD we have obtained exact analytical expressions for the eigenvalue density of the Dirac operator at fixed $\theta \ne 0$ for both one and two flavors. These results made it possible to explain how the different…

High Energy Physics - Lattice · Physics 2018-07-31 Mario Kieburg , Jacobus Verbaarschot , Tilo Wettig

We consider the quark-meson model with two quark flavors in a constant external magnetic field $B$ at finite temperature $T$ and finite baryon chemical potential $\mu_B$. We calculate the full renormalized effective potential to one-loop…

High Energy Physics - Phenomenology · Physics 2015-05-28 Jens O. Andersen , Rashid Khan

We apply a random matrix model to the study of the phase diagram of QCD with two colors, two flavors, and a small quark mass. Although the effects of temperature are only included schematically, this model reproduces most of the ground…

High Energy Physics - Phenomenology · Physics 2016-09-06 Benoit Vanderheyden , A. D. Jackson

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