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arXiv · 2502.12074

Lattice QCD Study of Pion Electroproduction and Weak Production from a Nucleon

Yu-Sheng Gao·Zhao-Long Zhang·Xu Feng·Lu-Chang Jin·Chuan Liu·Ulf-G. Meißner
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Abstract

Quantum fluctuations in QCD influence nucleon structure and interactions, with pion production serving as a key probe of chiral dynamics. In this study, we present a lattice QCD calculation of multipole amplitudes at threshold, related to both pion electroproduction and weak production from a nucleon, using two gauge ensembles near the physical pion mass. We develop a technique for spin projection and construct multiple operators for analyzing the generalized eigenvalue problem in both the nucleon-pion system in the center-of-mass frame and the nucleon system with nonzero momentum. The numerical lattice results are then compared with those extracted from experimental data and predicted by low-energy theorems incorporating one-loop corrections.

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Yu-Sheng Gao, Zhao-Long Zhang, Xu Feng, Lu-Chang Jin, Chuan Liu, Ulf-G. Meißner. 2025-02-17. Lattice QCD Study of Pion Electroproduction and Weak Production from a Nucleon. https://arxiv.org/abs/2502.12074

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