2025/09/19 by Shan Cheng, Lingyun Dai, Cheng, Shan +4
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions
paper · doi:10.48550/arxiv.2509.15659
openalex publication_date 2025/09/19 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03
We present a novel framework for analyzing four-body semileptonic weak decays, performing the first high-twist analysis of the Ds → [ ππ]\rm S form factors using light-cone distribution amplitudes for the isoscalar two-pion state (2πDAs). It is motivated by persistent tensions between phenomenological cascade analyses and QCD-based interpretations of the partonic structure of f0 meson. Our study reveals that the twist-3 2πDAs incorporate an asymmetry in the partial-wave expansion, a feature absent in single f0 distribution amplitudes, that drives a substantial cancellation between twist-2 and twist-3 contributions to the form factors. As a result, the predicted decay rate falls significantly below the experimental value. These findings indicate that the isoscalar two-pion system near the charm scale is not primarily a q q state, reviving the energy-dependent partonic structures of light scalar mesons by highlighting a fundamental limitation of the single-meson LCDA approach in describing such complex systems.