Quasi parton distribution functions at NNLO: flavor non-diagonal quark contributions

TL;DR

This paper calculates NNLO corrections to quasi-PDFs in LaMET, focusing on flavor non-diagonal quark channels, and derives the matching coefficient to improve understanding of nucleon structure from QCD first principles.

Contribution

It provides the first NNLO calculation of quasi-PDFs for flavor non-diagonal quark channels within LaMET, including the derivation of the matching coefficient.

Findings

Demonstrates LaMET factorization at NNLO accuracy.

Derives the matching coefficient between quasi-PDF and light-cone PDF.

Lays groundwork for a complete NNLO analysis of quasi-PDFs.

Abstract

We present a next-to-next-to-leading order (NNLO) calculation of the quasi parton distribution functions (Quasi-PDFs) in the large momentum effective theory (LaMET). We focus on the flavor non-diagonal 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.