English

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

High Energy Physics - Phenomenology 2024-08-01 v3 High Energy Physics - Experiment High Energy Physics - Lattice

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.

Keywords

Cite

@article{arxiv.2312.17228,
  title  = {Next-to-next-to-leading-order QCD corrections to pion electromagnetic form factors},
  author = {Long-Bin Chen and Wen Chen and Feng Feng and Yu Jia},
  journal= {arXiv preprint arXiv:2312.17228},
  year   = {2024}
}

Comments

v3, 9 pages, 3 figures, 2 tables. The preceding version contains a mistake, and the two-loop hard-scattering kernel is corrected in the current version. Fig. 2 and Fig. 3 are redrawn, but phenomenological conclusion remains unchanged. Ancillary file containing the correct hard-scattering kernels through NNLO provided