Related papers: Pion-photon transition form factor using light-con…
Elastic and semileptonic transition form factors for the kaon and pion are calculated using the leading-order in a global-symmetry-preserving truncation of the Dyson-Schwinger equations and a momentum-independent form for the associated…
We use the world data on the pion form factor for space-like kinematics and a technique previously used to extract the proton transverse densities to extract the transverse pion charge density and its uncertainty due the incomplete…
We use dispersive techniques to address the behavior of the pion form factor as $Q^2 \to \infty$ and $Q^2 \to 0$. We perform the matching with the constraints of perturbative QCD and chiral perturbation theory in the high energy and low…
The electromagnetic form factor of the pion is calculated in a pseudoscalar field theoretical model which constituent quarks. We extract the form factor using the "+" component of the electromagnetic current in the light-cone formalism. For…
Recent measurement of the $\gamma\gamma^\ast$ form factor of the neutral pion in the high $Q^2$ region disagrees with {\em a priori} predictions of QCD-based calculations. We comment on existing explanations, and analyze a possibility that…
We study the pion electromagnetic and $\gamma^* + \pi^0 \to \gamma$ transition form factors at intermediate momentum transfer. We calculate soft, nonperturbative corrections to the leading perturbative amplitudes which arise from the $q\bar…
We perform an updated analysis of $e^+e^-\to\pi^+\pi^-$ cross-section data using a dispersive representation of the pion vector form factor. We show that the available data are compatible with the assumption that the form factor is free of…
The properties of the B-meson light-cone wave function up to next-to-leading order Fock state expansion have been studied through a comparative study of the $B\to \pi$, $K$ transition form factors within the $k_T$ factorization approach and…
We present an improved calculation on the pionic twist-3 distribution amplitudes $\phi^{\pi}_{p}$ and $\phi^{\pi}_{\sigma}$, which are studied within the QCD sum rules. By adding all the uncertainties in quadrature, it is found that…
We present an investigation of the electromagnetic pion form factor, $F_\pi(Q^2)$, at small values of the four-momentum transfer $Q^2$ ($\lesssim 0.25$ GeV$^2$), based on the gauge configurations generated by European Twisted Mass…
In the paper, we investigate the charmed meson rare decay process $D^+ \to \pi^+\nu\bar\nu$ by using QCD sum rules approach. Firstly, the pion twist-2 and twist-3 distribution amplitude $\xi$-moments $\langle\xi_{2;\pi}^n\rangle|_\mu$ up to…
We calculate the leading-twist O(alphas^2 beta0) corrections to the B to pi transition form factor f+(0) in light-cone sum rules. We find that, as expected, there is a cancellation between the O(alphas^2 beta0) corrections to fB f+(0) and…
Results of the Spectral Quark Model for the gravitational, electromagnetic, and transition form factors of the pion are discussed. In this model both the parton distribution amplitude and the parton distribution function are flat, in…
We report on the perturbative $O(\alpha_s)$ correction to the light-cone QCD sum rule for the $B\to \pi$ transition form factor $f^+$. The correction to the product $f_Bf^+$ in leading twist approximation is found to be about 30%, that is…
We consider two simple covariant models for pions (one with scalar and the other with spin-1/2 constituents). Pion generalized parton distributions are derived by integration over the light-cone energy. The model distributions are…
The lightest meson, the pion, features two faces -- one is the elementary Goldstone boson of QCD and the other is the structured bound state of quarks and gluons. To accommodate both in a single light-front wave function in the valence…
The pion scalar, vector and tensor form factors are calculated within a symmetry-preserving contact interaction model (CI) of quantum chromodynamics (QCD), encompassed within a Dyson-Schwinger and Bethe-Salpeter equations approach. In…
We present a general representation for the nucleon distribution amplitudes and for the nucleon to pion transition distribution amplitudes in terms of light-cone wave functions. We apply our formalism to a light-cone constituent quark model…
Measurements and theoretical calculations of meson form factors are essential for our understanding of internal hadron structure and QCD, the dynamics that bind the quarks in hadrons. The pion electromagnetic form factor has been measured…
We study the anomalous electromagnetic pion form factor $F_{\pi^0\gamma^*\gamma^*}$ with a set of holographic models. By comparing with the measured value of the linear slope, some of these models can be ruled out. From the remaining models…