Related papers: Two-loop contribution to the pion transition form …
We provide an in-depth analysis of the $\pi$ distribution amplitude in terms of two different Gegenbauer representations. Detailed predictions for the $\pi-\gamma$ transition form factor are presented, obtained with light-cone sum rules.…
By means of QCD sum rules in local-duality limit, we analyze the behaviour of the form factors for the transitions of a real and a virtual photon to some pseudoscalar meson as functions of the involved momentum transfer. Except for the…
We derive an expression for the $B\to\pi$ transition form factor only depending the twist-3 distribution amplitudes by choosing an adequate chiral current correlator in the light-cone QCD sum rules. Our result show that the contribution…
The CLEO experimental data on the $\pi\gamma$ transition are analyzed to next-to-leading order accuracy in QCD perturbation theory using light-cone QCD sum rules. By processing these data along the lines proposed by Schmedding and Yakovlev,…
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…
Based on $2.93\,\text{fb}^{-1}$ of $e^+e^-$ collision data taken with the BESIII detector at a center-of-mass energy of $3.773\,\text{GeV}$, the two-photon fusion process $e^+e^-\to e^+e^-\pi^0$ is investigated using a single-tag approach.…
In view of the first measurement of the branching fraction for J/psi --> pi^0 e^+ e^- by the BESIII collaboration, we analyze what can be learnt on the corresponding transition form factor using dispersion theory. We show that light-quark…
We present the status of the Mainz group's lattice QCD calculation of the pion transition form factor $\mathcal{F}_{\pi^0\gamma^\ast\gamma^\ast}$, which describes the interaction of an on-shell pion with two off-shell photons. This form…
The holographic QCD prediction for the pion distribution amplitude (DA) $\phi_{hol}(u)$ is used to compute the pion spacelike electromagnetic form factor $F_{\pi}(Q^2)$ within the QCD light-cone sum rule method. In calculations the pion's…
We review the determination of the NLO Brodsky-Lepage-Mackenzie (BLM) renormalization scale for the pion transition form factor. We argue that the prediction for the pion transition form factor is independent of the factorization scale at…
Within the framework of QCD light-cone sum rules (LCSR), we calculate the form factor for $B{\to}D l\tilde{\nu}$ transitions with chiral current correlator. The resulting form factor depends on the distribution amplitude(DA) of the…
We apply the so-called conformal subtraction scheme to predict perturbatively exclusive processes beyond leading order. Taking into account evolution effects, we study the scheme dependence for the photon-to-pion transition form factor and…
The pion and kaon electromagnetic form factors $F_{M}(Q^2)$ are calculated at the leading order of pQCD using the running coupling constant method. In computations dependence of the meson distribution amplitudes on the hard scale $Q^2$ is…
In this review, we discuss the calculation of the $B\to P,V$ form factors within the framework of the light-cone sum rules with the light-cone distribution amplitudes of the $B$ meson. A detailed introduction to the definition, scale…
Recent BABAR results on two-photon processes are presented. A high statistics study of the two-photon production of the charmonium states eta_c and eta_c(2S) is performed. The mass and width of eta_c and eta_c(2S) are measured; the ratio of…
The form factors of the semileptonic $B\to \pi\pi\ell\bar\nu$ decay are calculated from QCD light-cone sum rules with the distribution amplitudes of dipion states. This method is valid in the kinematical region, where the hadronic dipion…
New sum rules for $B\to \pi,K $ and $B\to \rho,K^*$ form factors are derived from the correlation functions expanded near the light-cone in terms of B-meson distribution amplitudes. The contributions of quark-antiquark and…
$B_{(s)}$ semi-leptonic decays to the light scalar meson, $B_{(s)}\to S l\bar{\nu}_l, S l \bar{l}\,\,(l=e,\mu,\tau)$, are investigated in the QCD light-cone sum rules (LCSR) with chiral current correlator. Having little knowledge of…
We study the pion form factor in a broad range of spacelike momentum transfers within the local-duality version of QCD sum rules. We make use of the recently calculated two-loop double spectral density of the $<AVA>$ correlator including…
We compute the $\Lambda_b \to \Lambda$ transition form factors using light-cone sum rules based on $\Lambda$-baryon distribution amplitudes, including contributions up to twist--6. The analysis is performed for pseudoscalar, vector, and…