Related papers: Pion to photon transition form factors with basis …
In the scaling regime, amplitudes for backward virtual Compton scattering and hadron annihilation into two photons depend on structure functions that describe the hadron-photon transition at the partonic level. We construct simple…
We obtain the electromagnetic form factors of the $\gamma N\Delta$ transition by analyzing recent pion-electroproduction data using a fully relativistic dynamical model. Special care is taken to satisfy Ward-Takahashi identities for the…
We investigate the two-particle twist-3 distribution amplitudes (DAs) of the pseudoscalar mesons, in particular pseudoscalar ($\phi^P_{3;M}(x)$) and pseudotensor ($\phi^\sigma_{3;M}(x)$) DAs of the pion and kaon, in the light-front quark…
It is noted that the low-energy behavior of the pion-photon transition form factor $F_{\pi\gamma}(Q^2)$ is sensitive to the transverse distribution of the pion wavefunction, and its high-energy behavior is sensitive to the longitudinal one.…
The form factors for the transitions pi-photon, eta-photon, eta'-photon and etac-photon are analyzed within the modified perturbative approach in which quark transverse degrees of freedom are retained. The results for the form factors are…
The pion electromagnetic form factor is calculated within the QCD light-cone sum rule method and using a renormalon model for the higher twist distribution amplitudes (DAs). The theoretical predictions are compared with the experimental…
We study the scaling regime of nucleon-anti-nucleon annihilation into a deeply virtual photon and a photon or meson, \bar p N -> gamma ^* pi, \bar p N -> gamma ^* gamma, in the forward direction. The leading twist amplitude factorizes into…
We have applied the light-front formalism to calculate the electromagnetic form factors for the pion and the kaon from two models at low and high energies in order to explore the differences between such models. We have also compared the…
We suggest to probe the pion light-cone distribution amplitude, applying a dispersion relation for the pion electromagnetic form factor. Instead of the standard dispersion relation, we use the equation between the spacelike form factor…
The structure of the pion wave function in the relativistic constituent quark model is investigated in the explicitly covariant formulation of light-front dynamics. We calculate the two relativistic components of the pion wave function in a…
Baryon to meson transition distribution amplitudes (TDAs), non-diagonal matrix elements of the nonlocal three quark operator between a nucleon and a meson state, extend the concept of generalized parton distributions. These non-perturbative…
We prove factorization theorem for the processes $\pi\gamma^*\to\gamma$ and $\pi\gamma^*\to\pi$ to leading twist in the covariant gauge by means of the Ward identity. Soft divergences cancel and collinear divergences are grouped into a pion…
We recalculate the pion electromagnetic form factor based on the perturbative QCD formalism that includes the Sudakov resummation. We take into account the evolution of the pion wave function in $b$, which represents the transverse extent…
The electromagnetic form factor of the pion is calculated in the "point-form" of relativistic quantum mechanics using simple, phenomenological wave functions. It is found that the squared charge radius of the pion is predicted one order of…
We analyze the higher-twist effects and the SU(3)-flavour symmetry breaking in the correlation functions used to calculate form factors of pseudoscalar mesons in the QCD light-cone sum rule approach. It is shown that the Ward identities for…
Using non-local chiral quark model and currents satisfying Ward-Takahashi identities we analyze Distribution Amplitudes (DA) of photon and pion-to-photon Transition Distribution Amplitudes (TDA) in the low energy regime. Photon DA's are…
In this work, we perform a detailed study of transition form factors for axial-vector meson production via the two-photon fusion process $\gamma^* \gamma^* \to 1^{++}$, with space-like virtual photons in the initial state and a $P$-wave…
The exclusive production of \pi\pi and \pi\rho in hard \gamma^{\star}\gamma scattering in the forward kinematical region where the virtual photon is highly off-shell are studied through the \gamma\to\pi^- Transition Distribution Amplitudes.…
We study the pion electromagnetic form factor in the modulus squared dispersion relation, and do the model independent extraction of the most important nonperturbative parameters in pion light-cone distribution amplitude. The motivation of…
We extend recently developed methods used for determining the electromagnetic charge radius and $a_\mu^{\pi\pi}$ to obtain a determination of the electromagnetic form factor of the pion, $F_\pi^V(t)$, in several significant kinematical…