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arXiv · 2404.04412

QCD Predictions for Meson Electromagnetic Form Factors at High Momenta: Testing Factorization in Exclusive Processes

Heng-Tong Ding·Xiang Gao·Andrew D. Hanlon·Swagato Mukherjee·Peter Petreczky·Qi Shi·Sergey Syritsyn·Rui Zhang·Yong Zhao
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Abstract

We report the first lattice QCD computation of pion and kaon electromagnetic form factors, $F_M(Q^2)$, at large momentum transfer up to 10 and 28 $\mathrm{GeV}^2$, respectively. Utilizing physical masses and two fine lattices, we achieve good agreement with JLab experimental results at $Q^2 \lesssim 4~\mathrm{GeV}^2$. For $Q^2 \gtrsim 4~\mathrm{GeV}^2$, our results provide $\textit{ab-initio}$ QCD benchmarks for the forthcoming experiments at JLab 12 GeV and future electron-ion colliders. We also test the QCD collinear factorization framework utilizing our high-$Q^2$ form factors at next-to-next-to-leading order in perturbation theory, which relates the form factors to the leading Fock-state meson distribution amplitudes. Comparisons with independent lattice QCD calculations using the same framework demonstrate, within estimated uncertainties, the universality of these nonperturbative quantities.

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Heng-Tong Ding, Xiang Gao, Andrew D. Hanlon, Swagato Mukherjee, Peter Petreczky, Qi Shi, Sergey Syritsyn, Rui Zhang, Yong Zhao. 2024-04-05. QCD Predictions for Meson Electromagnetic Form Factors at High Momenta: Testing Factorization in Exclusive Processes. https://doi.org/10.1103/physrevlett.133.181902

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