相关论文: A renewed look at eta' in medium

We report on the $U_{A}(1)$ symmetry restoration resulting due to temperature dependence of the coefficient c(T) for the Kobayashi-Maskawa-'t Hooft determinant (KMT) term in a modified 2+1 flavor Polyakov loop quark meson model having…

We investigate the restoration of chiral SU$(3)\otimes$SU$(3)$ and axial U$_A$(1) symmetries, at finite temperature and density, in the framework of the three flavor Nambu-Jona-Lasinio model with anomaly. We implement a temperature…

Modulo the scale of spontaneous breaking of Peccei-Quinn symmetry, the axion mass $m_a(T)$ is given by the QCD topological susceptibility ${\chi}(T)$ at all temperatures $T$. From an approach tying the $U_A(1)$ and chiral symmetry breaking…

We study the restoration of chiral symmetry in linear sigma models with two quark flavors. The models taken into consideration have a U(2)_L x U(2)_R and an O(4) internal symmetry. The physical mesons of these models are sigma, pion, eta…

We calculate the thermally averaged rates for the $\eta$-$\pi$ conversion and $\eta$ scattering using the Di Vecchia-Veneziano model and t' Hooft model, which incorporate explicitly the $U(1)_A$ anomaly. Assuming an exponential suppression…

We describe in-medium properties of hadrons in dense matter near chiral restoration using a Wilsonian matching to QCD of an effective field theory with hidden local symmetry at the chiral cutoff $\Lambda$. We find that chiral symmetry is…

Using the trace anomaly and low energy relations, as well as the Witten-Veneziano formula for the mass of the $\eta'$ meson, we have developed a formalism which makes it possible to express the gluon condensate, the topological…

The catalysis of chiral symmetry breaking in the massless weakly coupled QED in a magnetic field at finite temperature is studied. The temperature of the symmetry restoration is estimated analytically as $T_c\simeq m_{dyn}$, where $m_{dyn}$…

We propose a mechanism which explains the masses of $\eta$ and $\eta'$ mesons without invoking the explicit violation of $U(1)_A$ symmetry by the chiral anomaly. It is shown that the U(1) problem, the problem for which the prediction of…

The ratio of the sigma mass to the pion mass at finite temperatures and densities provides for a quantitative signal of chiral symmetry breaking. We calculate this ratio by using an extension to finite chemical potential of the field…

Chiral restoration phase transition in hot and/or dense hadronic matter is discussed in terms of the BR scaling based on chiral symmetry and scale anomaly of QCD. The precise connection between the scalar field that figures in the trace…

The behavior of neutral pseudoscalar mesons $\pi^0, \eta$ and $\eta'$ in hot and dense matter is investigated, in the framework of the three flavor Nambu-Jona-Lasinio model. Three different scenarios are considered: zero density and finite…

We discuss the fate of the axial U(1) symmetry in 2-flavor QCD at finite temperature, where the non-singlet chiral symmetry is restored. We first summarize the previous theoretical investigation on the relation between the eigenvalue…

In the introduction, we will discuss the symmetries of QCD, its breaking in the physical vacuum and its restoration at finite temperature and/or density. Then we will discuss what exact relations can be made between chiral symmetry…

It is widely believed that chiral symmetry is restored not only at high temperatures, but also at high nuclear densities. The drop of the order parameter of the chiral phase transition, the chiral condensate, with density has indeed been…

Modifications of baryon properties due to the restoration of the chiral symmetry in an external hot and dense baryon medium are investigated in an effective chiral quark-meson theory. The nucleon arises as a soliton of the Gell-Mann -…

The QCD vacuum shows the dynamical breaking of chiral symmetry. In the hot/dense QCD medium, the chiral order parameter such as $ < \bar q q > $ is expected to change as function of temperature $T$ and density $\rho$ of the medium, and its…

We present a study of the $\pi\pi$ scattering amplitude in the $\sigma$ and $\rho$ channels at finite temperature and nuclear density within a chiral unitary framework. Meson resonances are dynamically generated in our approach, which…

Using the unification of the chiral SU(3) model and QCD sum rules, we deduce the in-medium properties of $K^\pm_1$ meson. Within the chiral SU(3) model, medium modified gluon and quark condensates are evaluated through their interactions…

In this paper we study the $\eta'$ in $N_f=2+1+1$ lattice QCD simulations at finite temperature. Results are obtained from the analysis of the gluonic defined topological charge density correlator after gradient flow. Our results indicate…