  We use light-cone QCD sum rules to calculate the pion-photon transition form
factor, taking into account radiative corrections up to the
next-to-next-to-leading order of perturbation theory. We compare the obtained
predictions with all available experimental data from the CELLO, CLEO, and the
BaBar Collaborations. We point out that the BaBar data are incompatible with
the convolution scheme of QCD, on which our predictions are based, and can
possibly be explained only with a violation of the factorization theorem. We
pull together recent theoretical results and comment on their significance.

High Energy Physics - Phenomenology