Related papers: Space-like and time-like pion electromagnetic form…
We developed a model for the pion light-front wave function (LFWF) that incorporates valence, sea and gluon degrees of freedom. Using the LFWF overlap representation, we derived parametrizations for the pion parton distribution functions…
The behavior of the transition pion form factor for processes \gamma^*\gamma -> \pi^0 and \gamma^* \gamma^* -> \pi^0 at large values of space-like photon momenta is estimated within the nonlocal covariant quark-pion model. It is shown that,…
The electromagnetic form factor of the pion in the space-like region, and at finite temperature, $F_{\pi}(Q^{2},T)$, is obtained from a QCD Finite Energy Sum Rule. The form factor decreases with increasing T, and vanishes at some critical…
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…
The $\gamma^\ast \gamma \to \pi^0$ transition form factor, $G(Q^2)$, is computed on the entire domain of spacelike momenta using a continuum approach to the two valence-body bound-state problem in relativistic quantum field theory: the…
Within the framework of light-front field theory, we reassess the electromagnetic form factors of the pion and kaon. Comparison with experiment is made for the full range of momentum transfer, q^2<0, including recent data. The light-front…
We evaluate the vector and scalar form factor of the pion in the presence of virtual photons at next-to-leading order in two-flavor chiral perturbation theory. We also consider the scalar and tensor pion form factors of the energy-momentum…
We study the electromagnetic pion form factor and the VV - AA two point function for momenta -(600 MeV)^2 < q^2 < (600 MeV)^2 and we note the similarity between vector meson dominance and two versions of the free constituent quark model.…
We calculate the transition form factor of the neutral pion where one photon is virtual and another photon is real in the model where the light constituent quark mass and the quark-pion vertex are taken to be momentum independent. Radiative…
We extend our relativistic theory of electroweak properties of composite systems to describe simultaneously the gravitational form factors of hadrons. The approach is based on a version of the instant-form relativistic quantum mechanics and…
We compute the gravitational form factors (GFFs) of the pion and kaon using their light-front wave functions within the Basis Light-Front Quantization framework. The wave functions are obtained by solving a light-front effective Hamiltonian…
We study the transition form factors between pseudoscalar and vector mesons using a covariant fermion field theory model in $(3+1)$ dimensions. Performing the light-front calculation in the $q^+ =0$ frame in parallel with the manifestly…
A variety of strong and electroweak interaction properties of the pion and the light scalar sigma meson are computed in a relativistic quark model. Under the assumption that the resulting coupling of these mesons to the constituent quarks…
We explore the possibility to verify vector meson dominance for the nucleon by measuring the half-off-shell form factor in the vector-meson mass region. Cross sections for the process $\gamma p \rightarrow p + e^+e^-$ be presented.
The charge form factor of the pion is calculated for momentum transfer range of Jefferson Lab experiments. The approach is based on the instant form of the relativistic Hamiltonian dynamics. It is shown that the form-factor dependence on…
We study the influence of non-valence quark-pair contributions in weak transition form factors of heavy-light mesons. Form factors are first calculated for spacelike momentum transfers in a reference frame where such contributions are…
Results are presented from an ongoing study of the $\rho$ resonance. The focus is on CLS 2-flavour ensembles generated using $\mathcal{O}(a)$ improved Wilson fermions with pion masses ranging from $265$ to $437$ $\mathrm{MeV}$. The energy…
We investigate the electroweak form factors and semileptonic decay rates of pseudoscalar and vector mesons using the light-front constituent quark model. Our method of analytic continuation in the Drell-Yan-West (q^+=q^0+q^3=0) frame to…
The recently evaluated two-pion contribution to the muon g-2 and the phase of the pion electromagnetic form factor in the elastic region, known from \pi\pi scattering by Fermi-Watson theorem, are exploited by analytic techniques for finding…
Employing the Bethe-Salpeter formalism, we present a computation of the space-like baryonic form factor for the pion and kaon. In the exact isospin-symmetric limit this observable is forbidden by $G$-parity, so that any nonzero signal…