Related papers: Vacuum Properties of Mesons in a Linear Sigma Mode…
Within a linear sigma model framework, possible mixing between two chiral nonets (a two quark nonet, and a four quark nonet) below 2 GeV is studied. Incorporating the U(1)$_A$ behavior of the underlying QCD, and working in the isospin…
The pion scalar form factor along with all existing S-wave iso-scalar $\pi\pi$-scattering phase shift data in the elastic region up to $1 {\rm GeV}^2$ are applied for a determination of the $f_0(500)$ and $f_0(980)$ meson parameters…
Zero temperature properties of an (axial-) vector meson extended linear sigma model are discussed, concerning on the possible different realizations of the axial anomaly term. The different anomaly terms are compared with each other on the…
Masses and decay constants of scalar $D_0$ and $D_{s0}$ mesons in isospin asymmetric strange hadronic matter at finite temperature are evaluated using QCD sum rules and chiral SU(3) model. In-medium light quark condensates, $\left\langle…
Vacuum and thermal properties of pseudoscalar and vector charm mesons are analyzed within a self-consistent many-body approach, employing a chiral effective field theory that incorporates heavy-quark spin symmetry. Upon unitarization of the…
We present lattice results for the form factors relevant in the K -> pion and D -> pion semileptonic decays, obtained from simulations with two flavors of dynamical twisted-mass fermions and pion masses as light as 260 MeV. For K -> pion…
We discuss the link between the chiral symmetry of QCD and the numerical results of the light-front quark model (LFQM), analyzing both the two-point and three-point functions of a pseudoscalar meson from the perspective of the vacuum…
The worldline representation of the one loop fermionic effective action is used to obtain the vertex operator for the pion and the sigma in QCD strings. The vertex operator of the scalar sigma is distinguished from that of the pseudo-scalar…
The present talk consists of two parts. The first one is allocated for consideration of the dimension of bilocal meson fields for quark-antiquark meson systems, which have been so far treated as the bosonic fields independent of constituent…
We calculate the mass of the vector meson in the chiral symmetry restored vacuum. This is accomplished by separating the four quark operators appearing in the vector and axial vector meson sum rules into chiral symmetric and symmetry…
Electromagnetic decays of the scalar mesons are shown to be constrained by chiral symmetry as a consequence of the fact that, in the chiral limit, the two and three-point functions $<SS-PP>$ and $<VVS>$ satisfy super-convergent dispersion…
This review of the quark-level linear \sigma model is based upon the dynamical realization of the pseudoscalar and scalar mesons as a linear representation of SU(2) x SU(2) chiral symmetry, with the symmetry weakly broken by current quark…
We derive the pion mass and the elastic pion-pion scattering amplitude in the QCD theta-vacuum up to next-to-leading order in chiral perturbation theory. Using the modified inverse amplitude method, we study the theta-dependence of the mass…
We study the chiral dynamics of vector mesons in two-flavor QCD in vacuum by utilizing a functional renormalization group approach. This allows us to capture the dynamical transition from the quark-gluon phase at high energies to the…
Previous work relating the flavour variation of the chiral order parameters $F_\pi$, $<\bar u u>$ and S-wave scattering data, based on chiral sum rules and chiral perturbation theory at order $p^4$, is extended to include $O(p^6)$…
A consistent description of the pi0 pi0 invariant mass distribution in the phi(1020) -> f0(980) gamma -> pi0 pi0 gamma decay and the pi0 eta in phi(1020) -> a0(980) gamma -> pi0 eta gamma is suggested. A search for the consequences of the…
The behavior of $\pi^0$ meson properties in the presence of a uniform external magnetic field is studied in the context of a nonlocal extension of the Polyakov-Nambu-Jona-Lasinio model. The analysis includes the $\pi^0$ mass, the effective…
Two photon decay widths of the $J^P = O^+$ scalar mesons $a_{0} (980)$, $f_{0}(980)$, $f_{0}(1370)$ and $\chi_{c0}$ are calculated in a covariant model which is characterized by the quark - antiquark structure. Previously such models were…
We present a chirally symmetric hadronic model for the vector and axial-vector correlators in vacuum. The dominant contributions to these correlators come from intermediate pions, rho and a_1 mesons which are calculated in one-loop…
An extended linear sigma model with mesons (q\bar{q} states) and baryons (qqq states) is presented. The model contains a low energy multiplet for every hadronic particle type, namely a scalar, a pseudoscalar, a vector, and an axialvector…