Quasiparton distribution functions at NNLO: Flavor nondiagonal quark contributions

Abstract

We present a next-to-next-to-leading order (NNLO) calculation of the quasiparton distribution functions (quasi-PDFs) in the large momentum effective theory (LaMET). We focus on the flavor nondiagonal quark-quark channel and demonstrate the LaMET factorization at the NNLO accuracy in the modified minimal subtraction scheme. The matching coefficient between the quasi-PDF and the light-cone PDF is derived. This provides a first step towards a complete NNLO analysis of quasi-PDFs and to better understand the nucleon structures from the first principle of QCD.