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Title: Parton Distribution Functions and Lattice QCD
Recently, there have been rapid developments in lattice-QCD calculations of proton structure, especially in the parton distribution functions (PDFs). We overcame a longstanding obstacle and for the first time in lattice-QCD are able to directly calculate the Bjorken- x dependence of the quark, helicity and transversity distributions. The PDFs are obtained using the large-momentum effective field theory (LaMET) framework where the full Bjorken- x dependence of finite-momentum PDFs, called “quasi-PDFs”, can be calculated on the lattice. The quasi-PDF nucleon matrix elements are renormalized non-perturbatively in RI/MOM-scheme. Following a nonperturbative renormalization of the parton quasi-distribution in a regularization-independent momentum-subtraction scheme, we establish its matching to the $$ \overline {{\rm{MS}}} $$ PDF and calculate the non-singlet matching coefficient at next-to-leading order in perturbation theory. In this proceeding, I will show the progress that has been made in recent years, highlighting the latest state-of-the art PDF calculations at the physical pion mass. Future impacts on the large- x global PDF fits are also discussed.  more » « less
Award ID(s):
1653405
PAR ID:
10097103
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
EPJ Web of Conferences
Volume:
206
ISSN:
2100-014X
Page Range / eLocation ID:
01003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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