Parton distributions are an important input for understanding interactions with hadrons in terms of the underlying interactions of quarks and gluons. Until recently, parton distributions could not be determined directly from QCD. I will present results from a proposal of how to treat matrix elements calculable from ab-initio Lattice QCD as factorizable observables, which can be separated as experimental cross sections into parton distributions and perturbatively calculable kernels. These results can also be combined with experimental cross sections to expand the datasets for global analysis. The well known case of the unpolarized nucleon distribution has been used to study systematic errors in thecalculation, while ongoing and future work will be used to determine less precise distributions.
Joe Karpie recently earned his PhD at the College of William and Mary in 2019. He was working closely with the Theory Center at Jefferson Lab on the calculation of parton distributions from Lattice QCD, which is the subject of this presentation. He is currently a post-doc at Columbia University changing his focus to properties of Kaon decays. Particularly, he is working on non-perturbative corrections to the CP violation parameter \epsilon_K from Lattice QCD.