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arXiv · 2312.17228

Next-to-next-to-leading-order QCD corrections to pion electromagnetic form factors

Long-Bin Chen·Wen Chen·Feng Feng·Yu Jia
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Abstract

We investigate the next-to-next-to-leading order (NNLO) QCD radiative corrections to the pion electromagnetic form factor with large momentum transfer. We explicitly verify the validity of the collinear factorization to two-loop order for this observable, and obtain the respective IR-finite two-loop hard-scattering kernel in the closed form. The NNLO QCD correction turns to be positive and significant. Incorporating this new ingredient of correction, we then make a comprehensive comparison between the finest theoretical predictions and numerous pion form factor measurements in both space-like and time-like regions. Our phenomenological analysis provides strong constraint on the second Gegenbauer moment of the pion light-cone distribution amplitude (LCDA) obtained from recent lattice QCD studies.

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Long-Bin Chen, Wen Chen, Feng Feng, Yu Jia. 2023-12-28. Next-to-next-to-leading-order QCD corrections to pion electromagnetic form factors. https://arxiv.org/abs/2312.17228

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