We present for the first time complete next-to-next-to-leading-order coefficient functions to match flavor nonsinglet quark correlation functions in position space, which are calculable in lattice QCD, to parton distribution functions (PDFs). Using PDFs extracted from experimental data and our calculated matching coefficients, we predict valence-quark correlation functions that can be confronted by lattice QCD calculations. The uncertainty of our predictions is greatly reduced with higher order matching coefficients. By performing Fourier transformation, we also obtain matching coefficients for corresponding quasi-PDFs and pseudo-PDFs. Our method of calculations can be readily generalized to evaluate the matching coefficients for sea-quark and gluon correlation functions, making the program to extract partonic structure of hadrons from lattice QCD calculations comparable with and complementary to that from experimental measurements.

中文翻译：

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从晶格QCD计算中提取下一个到下一个领先的Parton分布函数

我们首次提出了完整的，从下到前的前导系数函数，以将可在晶格QCD中计算的位置空间中的风味非单夸克相关函数与parton分布函数（PDF）进行匹配。使用从实验数据中提取的PDF和我们计算出的匹配系数，我们可以预测晶格QCD计算可能遇到的价-夸克相关函数。使用更高阶的匹配系数可以大大降低我们预测的不确定性。通过执行傅立叶变换，我们还获得了对应的准PDF和伪PDF的匹配系数。我们的计算方法可以很容易地推广到评估夸克和胶子相关函数的匹配系数，