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We update the theoretical framework for the QCD calculation of transition form factors $gamma^*gammatoeta$ and $gamma^*gammatoeta$ at large photon virtualities including full next-to-leading order analysis of perturbative corrections, the charm quark contribution, and taking into account SU(3)-flavor breaking effects and the axial anomaly contributions to the power-suppressed twist-four distribution amplitudes. The numerical analysis of the existing experimental data is performed with these improvements.
Calculations of the magnetic dipole, electric quadrupole and Coulomb quadrupole amplitudes for the transition $gamma Nto Delta$ are presented both in quenched QCD and with two flavours of degenerate dynamical quarks.
The form factors of $gamma^* N rightarrow Delta(1600)$ transition is calculated within the light-cone sum rules assuming that $Delta^+(1600)$ is the first radial excitation of $Delta(1232)$. The $Q^2$ dependence of the magnetic dipole $tilde{G}_M(Q^2
The light-front quark model analysis of the meson-photon transition form factor $F_{Pgamma} (Q^2)$ amenable both for the spacelike region ($Q^2 >0$) and the timelike region ($Q^2 <0$) provides a systematic twist expansion of $Q^2 F_{Pgamma} (Q^2)$ fo
The nucleon electromagnetic form factors are calculated in light cone QCD sum rules framework using the most general form of the nucleon interpolating current. Using two forms of the distribution amplitudes (DAs), predictions for the form factors are
We derive light-cone sum rules for the electromagnetic nucleon form factors including the next-to-leading-order corrections for the contribution of twist-three and twist-four operators and a consistent treatment of the nucleon mass corrections. The e