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arXiv · 0909.5128

Two-loop contribution to the pion transition form factor vs. experimental data

S. V. Mikhailov·N. G. Stefanis
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Abstract

We present predictions for the pion-photon transition form factor, derived with the help of light-cone sum rules and including the main part of the NNLO radiative corrections. We show that, when the Bakulev-Mikhailov-Stefanis (BMS) pion distribution amplitude is used, the obtained predictions agree well with the CELLO and the CLEO data. We found that no model distribution amplitude can reproduce the observed $Q^2$ growth of the new BaBar data, though the BMS model complies with several BaBar data points.

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S. V. Mikhailov, N. G. Stefanis. 2009-09-28. Two-loop contribution to the pion transition form factor vs. experimental data. https://doi.org/10.1016/j.nuclphysbps.2009.12.039

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