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We present an extended analysis of the data for the pion-photon transitionform factor from different experiments, CELLO, CLEO, and BaBar, and discussvarious theoretical approaches which try to reason from them. We focus on thedivergent behavior of the BaBar data for the pion and those for the$\eta(\eta')$ pseudoscalar mesons and comment on recently proposed explanationsfor this discrepancy. We argue that it is not possible at present toaccommodate these data within the standard QCD framework self-consistently.

Pion-Photon Transition Form Factor and Pion Distribution Amplitude in QCD: Facing the Enigmatic Behavior of the BaBar Data