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arXiv · 2406.19376

Higher-twist generalized parton distributions of the pion and kaon at zero skewness in the light-cone quark model

Abstract

We investigate the higher-twist generalized parton distributions (GPDs) of the pion and kaon at zero skewness by adopting the overlap representation within the light-cone formalism. Using the wave functions of pion and kaon deduced from a light-cone quark model (LCQM), we calculate the twist-3 and twist-4 GPDs $E_{2}(x,0,t)$, $G_{2}(x,0,t)$, $F_{3}(x,0,t)$ and $H_{3}(x,0,t)$ of valence quark inside the pion and kaon mesons. Numerical results for these higher-twist GPDs are presented. By taking the forward limit, we also present the numerical results for the corresponding twist-3 and twist-4 parton distribution functions (PDFs) $e(x)$ and $f_{3}(x)$ of pion and kaon. We further study the relations between $e(x)$ or $f_{3}(x)$ and the twist-2 unpolarized PDF $f_{1}(x)$.

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Xiaoyan Luan, Zhun Lu. 2024-06-27. Higher-twist generalized parton distributions of the pion and kaon at zero skewness in the light-cone quark model. https://arxiv.org/abs/2406.19376

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