3D Tomography (3DT) of Fundamental Partons
Joseph Torsiello, Temple University
Atomic nuclei and nucleons comprise more than 99% of the mass of visible matter. Given the role of nucleons in nature, understanding their structure is among the most important and active research areas in hadronic physics. Nucleons contain quarks and gluons (partons), which govern the latter's structure and properties. Partons are bound by the strong force, described by the theory of quantum chromodynamics (QCD). QCD is very complex and cannot be solved analytically. The only known theoretical approach to comprehensively study hadron structure is lattice QCD (LQCD). LQCD is a space-time discretization with billions of degrees of freedom, and one requires numerical simulations on supercomputers. Hadron structure is described in terms of distribution functions that provide a wealth of information on partons in terms of their position and momentum within the hadron. This constitutes 3D tomography. The research presented will be on the 3D tomography of the pion and the kaon from LQCD, which is part of my thesis research. Such information is obtained through the generalized distribution functions (GPDs), complemented by the transverse-momentum dependent distributions; both are limitedly studied. We aim to advance knowledge on GPDs using numerical simulations of QCD, based on a novel approach to fully determine GPDs in the 3D parameter space. This is non-trivial and demands cutting-edge fast algorithms and access to large-scale computing resources. Such a project will impact our understanding of the hadrons from first principles, which remains a long-term goal of nuclear physics, and the science of JLab, RHIC, and EIC. Results from this project will contribute in several areas where the experimental data are limited or non-existing. We anticipate a great impact on the synergy between LQCD and global analyses of experiments, which can achieve a better constraint of GPDs.