We propose a data-driven approach to extract the Kaon leading-twist distribution amplitude (DA) from empirical information on the ratio of the neutral-to-charged kaon electromagnetic form factors, RK. Our study employs a two-parameter representation of the DA at ζ=2 GeV, designed to capture the expected broadening and asymmetry of the distribution, as well as the soft endpoint behavior predicted by quantum chromodynamics (QCD). Our leading-order analysis of the latest experimental measurements of RK reveals that the extracted DA exhibits a somewhat significant skewness, with the first symmetric moment approximately ⟨1−2x⟩K=0.082(7). On the other hand, the brodaness and general shape of the produced distributions show a reasonable consistency with contemporaty lattice and continuum QCD analyses. These findings highlight the importance of accurately determining the profile of the DA, especially the skewness and its relation to SUF(3) flavor symmetry breaking, as well as the inclusion of higher-order effects in the hard-scattering kernels for analyzing data at experimentally accessible scales.
@article{arxiv.2504.07372,
title = {Empirical Determination of the Kaon Distribution Amplitude},
author = {Lei Chang and Yu-Bin Liu and Khépani Raya and M. Atif Sultan},
journal= {arXiv preprint arXiv:2504.07372},
year = {2025}
}