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arXiv · 2608.00564

Pion-photon transition form factor with analytic coupling

I. A. Zemlyakov·I. L. Chuev·A. V. Kotikov
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Abstract

We investigate the pion-photon transition form factor within the framework of analytic QCD. A comparison is performed between experimental data and perturbative QCD based on conventional and analytic versions of perturbation theory with the ``massive'' form of the twist-four contribution. We show that conventional perturbation theory fails to reproduce the data, while the analytic version demonstrates good agreement with experiment.

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I. A. Zemlyakov, I. L. Chuev, A. V. Kotikov. 2026-08-01. Pion-photon transition form factor with analytic coupling. https://arxiv.org/abs/2608.00564

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