Theoretical Investigations in Hadron Physics

Kent State University, Kent OH

Investigators

Abstract

This three-year theoretical physics research program isolates and analyzes a variety of physical mechanisms underlying the structure of subatomic matter at the very small distances where quarks and gluons can be discerned. Interpretation of experiments at national facilities such as the CEBAF accelerator at the Jefferson Laboratory (JLab) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) requires the identification of dominant physical mechanisms as grounded in the relativistic quantum field theory known as Quantum Chromodynamics (QCD). In many cases, the time-consuming direct numerical simulation of this theory by lattice computational methods must be complemented by continuum models built on the integral and differential equations of the field theory. The present project extends the reach of one of the most successful continuum models of QCD by generalizing it into new domains of physical measurements and phenomena. These include flavor mixing in pseudoscalar mesons influenced by the axial anomaly, masses, decays and transition form factors of mesons containing one or two heavy quarks, and the quark structure functions of pions, kaons, and nucleons as measured by deep inelastic lepton scattering. Broader impacts include the cross-fertilization of nuclear and particle physics, a return on the investment in the experimental facilities at JLab and RHIC, and integration of research and education through the research training of graduate students in connection with undergraduate teaching. The interactions of graduate students with scientists who are prominent nationally and internationally is a contribution to the nation's infrastructure for research and education. The PI uses examples from this research program to illustrate key elements of core graduate classes in Quantum Mechanics and Nuclear and Particle Physics. The PI and a colleague supervise an informal seminar course for graduate students and postdoctoral associates to discuss and present aspects of QCD and field theory that underlie this research program. An existing Linkage Collaboration with Australian scientists, together with NSF funding for the U.S.-Mexican bilateral collaboration from the Office of International Science and Engineering, will enhance international cooperation in science research and education.