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

TL;DR

This paper presents a lattice QCD approach using heavy-quark operator product expansion to calculate moments of pion and kaon light-cone distribution amplitudes, advancing non-perturbative hadron structure understanding.

Contribution

It introduces the HOPE framework with a fictitious heavy quark to compute higher Mellin moments of LCDAs from lattice QCD, including new results for kaon moments.

Findings

First three kaon moments determined from lattice QCD.

Continuum-limit pion fourth moment obtained in quenched approximation.

Demonstrates feasibility of HOPE method for higher moments.

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.