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Title: Resummation for lattice QCD calculation of generalized parton distributions at nonzero skewness
A<sc>bstract</sc> Large-momentum effective theory (LaMET) provides an approach to directly calculate thex-dependence of generalized parton distributions (GPDs) on a Euclidean lattice through power expansion and a perturbative matching. When a parton’s momentum becomes soft, the corresponding logarithms in the matching kernel become non-negligible at higher orders of perturbation theory, which requires a resummation. But the resummation for the off-forward matrix elements at nonzero skewnessξis difficult due to their multi-scale nature. In this work, we demonstrate that these logarithms are important only in the threshold limit, and derive the threshold factorization formula for the quasi-GPDs in LaMET. We then propose an approach to resum all the large logarithms based on the threshold factorization, which is implemented on a GPD model. We demonstrate that the LaMET prediction is reliable for [−1 +x0,−ξ−x0] ∪ [−ξ+x0, ξ−x0] ∪ [ξ+x0,1 −x0], wherex0is a cutoff depending on hard parton momenta. Through our numerical tests with the GPD model, we demonstrate that our method is self-consistent and that the inverse matching does not spread the nonperturbative effects or power corrections to the perturbatively calculable regions.  more » « less
Award ID(s):
2209424
PAR ID:
10625091
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
APS
Date Published:
Journal Name:
Journal of High Energy Physics
Volume:
2025
Issue:
7
ISSN:
1029-8479
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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