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arXiv · 2603.03688

Parton physics from a heavy-quark operator product expansion: Dynamical lattice QCD calculation of moments of the pion and kaon light-cone distribution amplitudes

S. -P. Alex Chang·William Detmold·Anthony V. Grebe·Matías Gutiérrez-Escobari·Issaku Kanamori·C. -J. David Lin·Robert J. Perry·Yong Zhao
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Abstract

The light-cone distribution amplitude (LCDA) is a fundamental non-perturbative quantity for understanding hadron structure and exclusive scattering processes. We report on our calculation of the pion and kaon LCDAs using the heavy-quark operator product expansion (HOPE) framework. This method employs an OPE analysis of hadronic amplitudes through the inclusion of a fictitious valence heavy quark. In these proceedings, we report progress on the determination of the first three nontrivial Mellin moments of the kaon LCDAs from dynamical lattice QCD calculations, and we summarize the recently published continuum-limit result for the pion fourth Mellin moment obtained in the quenched approximation, thereby demonstrating the feasibility of the HOPE method for accessing higher moments.

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S. -P. Alex Chang, William Detmold, Anthony V. Grebe, Matías Gutiérrez-Escobari, Issaku Kanamori, C. -J. David Lin, Robert J. Perry, Yong Zhao. 2026-03-04. Parton physics from a heavy-quark operator product expansion: Dynamical lattice QCD calculation of moments of the pion and kaon light-cone distribution amplitudes. https://arxiv.org/abs/2603.03688

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