High Energy Physics Seminar
Speaker: Yong Zhao, MIT
Title: “Parton Distribution Functions from the Euclidean Lattice”
Refreshments available at 1:30 pm.
Date: Tue, 21 Nov 2017, 1:45 pm – 2:45 pm
Location: 1400 BPS Bldg.
Parton distribution functions (PDFs) are among the most important quantities for us to understand the hadron structure in high-energy scattering. The PDF is defined from light-cone correlation in QCD factorization theorems, so it is intrinsically Minkowskian and difficult to calculate from the Euclidean lattice theory, which is the only practical non-perturbative approach to solve QCD so far. The large momentum effective theory (LaMET) allows us to extract the x-dependence of the PDF from a space-like correlation – known as the quasi PDF – on the lattice, and it has motivated vigorous lattice studies in recent years. In this talk, I will describe the formalism of LaMET, and show how we can perform a systematic calculation of the PDF on the lattice by controlling the theoretical uncertainties in lattice renormalization, power corrections, and perturbative matching. With greater computational power in the future, we will eventually be able to compare first principle calculations of the PDF with experimental data.