The role of zero-mode contributions in the matching for the twist-3 PDFs $e(x)$ and $h_L(x)$

Abstract

The perturbative procedure of matching was proposed to connect parton quasi-distributions that are calculable in lattice QCD to the corresponding light-cone distributions which enter physical processes. Such a matching procedure has so far been limited to the twist-2 distributions. Recently, we addressed the matching for the twist-3 PDF $g_T(x)$. In this work, we extend our perturbative calculations to the remaining twist-3 PDFs, $e(x)$ and $h_L(x)$. In particular, we discuss the non-trivialities involved in the calculation of the singular zero-mode contributions for the quasi-PDFs.

Comments: 20 pages, 2 figures, results for zero-mode contributions partly revised, associated discussion modified