Double parton distribution functions (dPDFs), entering the double parton scattering (DPS) cross section, are unknown fundamental quantities encoding new interesting properties of hadrons. Here, the pion dPDFs are investigated within different holographic QCD quark models in order to access their basic features. Results of the calculations obtained within the AdS/QCD soft-wall approach, have been compared with predictions of lattice QCD evaluations of the pion two-current correlation functions. The present analysis confirms that double parton correlations, affecting dPDFs, are very important and not direct accessible from generalised parton distribution functions and electromagnetic form factors. The comparison between lattice data and quark model calculations unveils the relevance of the contributions of high partonic Fock states in the pion. Nevertheless, by using a complete general procedure, results of lattice QCD have been used, for the first time, to estimate the mean value of the so called \(\sigma _{eff}\), a relevant experimental observable for DPS processes. In addition, the results of the first calculations of the \(\rho \) meson dPDFs are discussed in order to make predictions.

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AdS / QCD软墙模型中介子的双重parton相关：与晶格数据的首次比较

进入双部分散射（DPS）横截面的双部分分布函数（dPDF）是未知的基本量，编码强子的新有趣性质。在这里，在不同的全息QCD夸克模型中对pion dPDF进行了研究，以访问其基本特征。在AdS / QCD软壁方法中获得的计算结果已与pion二次电流相关函数的点阵QCD评估预测进行了比较。本分析证实影响dPDF的双parton相关性非常重要，不能从广义的parton分布函数和电磁形状因子中直接访问。晶格数据和夸克模型计算之间的比较揭示了高介子Fock态在介子中贡献的相关性。\（\ sigma _ {eff} \），这是DPS流程可观察到的相关实验。另外，讨论了\（\ rho \）介子dPDF的第一次计算结果，以便进行预测。