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arXiv · 1208.4754

Pion-photon transition form factor in light-cone sum rules

A. V. Pimikov·A. P. Bakulev·S. V. Mikhailov·N. G. Stefanis
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Abstract

We extract constraints on the pion distribution amplitude from available data on the pion-photon transition form factor in the framework of light-cone sum rules. A pronounced discrepancy $(2.7-3)\sigma$ between the Gegenbauer expansion coefficients extracted from the CELLO, CLEO, and Belle experimental data relative to those from BaBar is found. Predictions for the pion-photon transition form factor are presented by employing a pion distribution amplitude obtained long ago from QCD sum rules with nonlocal condensates. These predictions comply with the Belle data but disagree with those of BaBar beyond 9 GeV$^2$.

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A. V. Pimikov, A. P. Bakulev, S. V. Mikhailov, N. G. Stefanis. 2012-08-23. Pion-photon transition form factor in light-cone sum rules. https://doi.org/10.1063/1.4763506

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