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arXiv · 1409.4311

Transition form factors $\gamma^*\gamma\to\eta$ and $\gamma^*\gamma\to\eta'$ in QCD

S. S. Agaev·V. M. Braun·N. Offen·F. A. Porkert·A. Schäfer
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Abstract

We update the theoretical framework for the QCD calculation of transition form factors $\gamma^*\gamma\to\eta$ and $\gamma^*\gamma\to\eta'$ at large photon virtualities including full next-to-leading order analysis of perturbative corrections, the charm quark contribution, and taking into account SU(3)-flavor breaking effects and the axial anomaly contributions to the power-suppressed twist-four distribution amplitudes. The numerical analysis of the existing experimental data is performed with these improvements.

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S. S. Agaev, V. M. Braun, N. Offen, F. A. Porkert, A. Schäfer. 2014-09-15. Transition form factors $\gamma^*\gamma\to\eta$ and $\gamma^*\gamma\to\eta'$ in QCD. https://doi.org/10.1103/physrevd.90.074019

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