Charged Pion Scattering With Massive QED

Casey Berger, University of North Carolina, Chapel Hill

An understanding of the strong nuclear force is essential to describing nature in a fundamental sense: Most of the mass of protons and neutrons that make up much of the universe's visible matter is due to the binding energy of the strong nuclear force, which holds the constituent quarks together. Lattice QCD (LQCD) is a non-perturbative lattice gauge method used to investigate many QCD phenomena that cannot be solved via analytic or perturbative methods. In addition to the strong nuclear force, the electromagnetic (QED) and weak nuclear forces must be included in calculations to understand the properties and structure of nuclei. While weak interactions can be treated perturbatively, the addition of long-ranged QED interactions presents an additional challenge. In this work, we investigate the inclusion of QED interactions on the collision of charged pions using a massive photon as a regulator. The QED interactions are added to previous configurations that calculated the strong interactions only and the results computed at multiple photon masses. The results are then extrapolated to the physical limit of a massless photon.

Abstract Author(s): Casey Berger, Chia Cheng Chang, Amy Nicholson, Michael Endres, Brian Tiburzi, Andre Walker-Loud