The pion parton distribution function, $u^{\pi}(x)$, is reexamined by a universal reparametrization function, $w_\tau(x)$, in the light-front holographic QCD (LFHQCD) approach. We show that, owing to the flexibility of $w_\tau(x)$, the large-$x$ behavior $u^{\pi}(x)\sim (1-x)^{2}$ can be contained within the LFHQCD formalism. From this fact, augmented by perturbative QCD and recent lattice QCD results, we state that such behavior cannot be excluded.

中文翻译：

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光前全息 QCD 中的 Pion Parton 分布函数

在光前全息 QCD (LFHQCD) 方法中，pion parton 分布函数 $u^{\pi}(x)$ 由通用重新参数化函数 $w_\tau(x)$ 重新检查。我们表明，由于 $w_\tau(x)$ 的灵活性，可以包含大 $x$ 行为 $u^{\pi}(x)\sim (1-x)^{2}$在 LFHQCD 形式主义中。根据这一事实，加上微扰 QCD 和最近的晶格 QCD 结果，我们声明不能排除这种行为。