PDF in PDFs from Hadronic Tensor and LaMET

TL;DR

This paper clarifies the proper definition of valence partons in PDFs within LaMET, resolving a phenomenological issue by focusing on connected insertions and elucidating the nature of strange partons as disconnected sea contributions.

Contribution

It demonstrates the equivalence of PDF classifications in QCD path-integral formulations and proposes a refined valence definition based on connected insertions.

Findings

Proper valence definition should be based on connected insertions.

Strange partons are identified as disconnected sea contributions.

The classification of PDFs is consistent across different QCD formulations.

Abstract

We point out a problem of the phenomenological definition of the valence partons as the difference between the partons and antipartons in the context of the NNLO evolution equations. After demonstrating that the classification of the parton degrees of freedom (PDF) of the parton distribution functions (PDFs) are the same in the QCD path-intergral formulations of the hadronic tensor and the quasi-PDF with LaMET, we resolve the problem by showing that the proper definition of the valence should be in terms of those in the connected insertions only. We also prove that the strange partons appear as the disconnected sea in the nucleon.