There have been rapid developments in parton distribution functions (PDFs) using lattice QCD for both precision moments and direct calculation of the Bjorken-$x$ dependence. In this talk, I show some progress along these directions and show some examples of how lattice-QCD calculations can play a significant role in improving our understanding of PDFs in the future.
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.
- Award ID(s):
- 1653405
- Publication Date:
- NSF-PAR ID:
- 10097103
- Journal Name:
- EPJ Web of Conferences
- Volume:
- 206
- Page Range or eLocation-ID:
- 01003
- ISSN:
- 2100-014X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Publisher's Version of Record
- https://doi.org/10.1051/epjconf/201920601003
