2024/07/30 by Chen, Long-Bin, Chen, Wen, Feng, Feng +1
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Lattice (hep-lat) #High Energy Physics - Phenomenology (hep-ph)
paper · doi:10.48550/arxiv.2407.21120
Among countless channels of hard exclusive reactions, the kaon electromagnetic form factors (EMFFs) are of special interest, which have been measured up to Q2 ∼ 50 \rm GeV2 in the timelike domain. The kaon EMFFs thereby serve an ideal platform to critically examine the validity and effectiveness of perturbative QCD (pQCD) in accounting for hard exclusive processes. In this work we confront the pQCD predictions that incorporate the next-to-next-to-leading-order (NNLO) perturbative corrections, with the available kaon EMFFs data set from experimental measurements and from lattice predictions. The inclusion of the NNLO corrections turns out to have a substantial and positive impact. If the profiles of the kaon light-cone distribution amplitudes (LCDAs) are taken from the recent lattice QCD prediction by \tt LPC Collaboration, the satisfactory agreement between theory and data can be reached for both charged and neutral kaons, in both spacelike and timelike large-Q2 domains.