Form factor $\pi^0 \gamma^* \gamma$ in lightcone sum rules combined with renormalization-group summation vs experimental data
Abstract
We consider the lightcone sum-rule (LCSR) description of the pion-photon transition form factor in combination with the renormalization group of QCD. The emerging scheme represents a certain version of Fractional Analytic Perturbation Theory and significantly extends the applicability domain of perturbation theory towards lower momenta GeV. We show that the predictions calculated herewith agree very well with the released preliminary data of the BESIII experiment, which have very small errors just in this region, while the agreement with other data at higher is compatible with the LCSR predictions obtained recently by one of us using fixed-order perturbation theory.
Keywords
Cite
@article{arxiv.1911.02845,
title = {Form factor $\pi^0 \gamma^* \gamma$ in lightcone sum rules combined with renormalization-group summation vs experimental data},
author = {C. Ayala and S. V. Mikhailov and A. V. Pimikov and N. G. Stefanis},
journal= {arXiv preprint arXiv:1911.02845},
year = {2019}
}
Comments
8 pages, 1 figure, talk presented at the "XXIV International Workshop on High Energy Physics and Quantum Field Theory" (22 - 29 September 2019, Sochi, Russia). A number of misprints are corrected