Speaker
Description
Understanding the internal structure and dynamics of protons and neutrons, the complex many-body systems consisting of strongly interacting quarks and gluons is at the core of exploring the visible matter universe. Gluons, which serve as mediator bosons of the strong interaction, play a key role in the nucleon’s mass and spin structures. In contrast, understanding of the gluon distributions and their roles in hadron structures remains some of the most challenging but fundamental issues in nuclear and particle physics. In this talk, we focus on the first lattice QCD determination of the gluon helicity parton distribution function with numerical evidence toward disfavoring negative gluon polarization in the nucleon and also discuss the reliability of overly constrained model-based extraction of unpolarized gluon distribution from limited lattice data. Using several machine learning algorithms on the Euclidean correlation functions, we demonstrate how one can alleviate the defining challenge of extracting quark-gluon PDFs from lattice data and point toward some critical future applications.