Related papers: Hadronic structure on the light-front VIII. Light …
In this presentation, we briefly review recent investigations on pion and kaon structures from the instanton vacuum. Starting from the low-energy QCD partition function, we have computed the Gasser-Leutwyler low-energy constants,…
The pion electric polarizability, \alpha^E_\pi^\pm, the leading order hadronic contribution to the muon anomalous magnetic moment, $a_\mu^{hvp 1} $, and the ratio of the difference to the sum of vector and axial-vector correlators,…
We discuss the effect of the instanton induced, six-fermion effective Lagrangian on the decays of the lightest scalar mesons in the diquark--antidiquark picture. This addition allows for a remarkably good description of light scalar meson…
Whereas the theoretical results for the dominant contributions to hadronic light-by-light scattering coming from pseudoscalar meson exchange have converged over the past years, the various published estimates of the contribution due to…
We consider the light-front holographic QCD with the light-front wave functions for mesons, modified for massive quarks. We evaluate the wave functions, distribution amplitudes, and form factors for $\pi$, $\rho$, $K$, and $J/\psi$ mesons…
The linear sigma model we present here describes the vacuum phenomenology of the $N_F=2$ scalar, pseudoscalar, vector and axial-vector mesons at energies $\simeq 1\text{ GeV}$. Together with a local $SU(2)_L\times U(1)_Y$ symmetry obtained…
The pion properties in symmetric nuclear matter are investigated with the Quark-Meson Coupling (QMC) Model plus the light-front constituent quark model~(LFCQM). The LFCQM has been quite successful in describing the properties of…
Starting from the bound state Hamiltonian equation of motion in QCD, we derive relativistic light-front wave equations in terms of an invariant impact variable $\zeta$ which measures the separation of the quark and gluonic constituents…
We review the approach to modeling soft hadron physics observables based on the Dyson-Schwinger equations of QCD. The focus is on light quark mesons and in particular the pseudoscalar and vector ground states, their decays and…
Low energy effective couplings of baryons' constituent quarks to light vector and axial mesons are derived by considering quark polarization for a dressed one gluon exchange quark interaction. The quark field is splitted into two…
In the framework of scalar-vector dominance we calculate the hadronic matrix elements of scalar and tensor effective quark currents induced by virtual leptoquark interactions. Combined bounds on the product of couplings and leptoquark…
We discuss scalar mesons properties on the light of chiral dynamics. Considering them as the chiral partners of pseudo-scalar mesons we propose an explanation to their unusual properties based on non-trivial vacuum effects coming from the…
The electromagnetic elastic form factors of pseudoscalar and vector mesons are analyzed for space-like momentum transfers in terms of relativistic quark models based on the Hamiltonian light-front formalism elaborated in different reference…
Nontrivial topological structures of non-Abelian gauge fields were discovered in the 1970's. Instanton solutions, describing vacuum tunneling through topological barriers, have fermionic zero modes which are at the origin of $^\prime$t…
An approach for describing the electromagnetic form factors of hadrons, in the space- and time-like regions, within a constituent quark model on the light front is shortly illustrated and calculations for the pion case are reported. Three…
Nucleon and pion electromagnetic form factors are evaluated in the spacelike region within a light-front constituent quark model, where eigenfunctions of a mass operator, reproducing a large set of hadron energy levels, are adopted and…
Unusual constituent quark axial current couplings to light vector mesons, $\rho$ and $\omega$, are derived in the vacuum and under weak magnetic field by considering a quark-antiquark interaction mediated by a non perturbative gluon…
We investigate the electroweak form factors and semileptonic decay rates of mesons using the constituent quark model based on the light-front degrees of freedom. Our results demonstrate the broader applicability of light-front approach…
The existing theory of hard exclusive QCD processes is based on two assumptions: (i) $factorization$ into a $hard\,block$ times light front distribution amplitudes (DA's); (ii) use of perturbative gluon exchanges within the hard block.…
A chiral extrapolation of the light vector meson masses in the up, down and strange quark masses of QCD is presented. We apply an effective chiral Lagrangian based on the hadrogenesis conjecture to QCD lattice ensembles of PACS-CS,…