The experimental research program has the overall goal of exploring the dynamics of few-body systems. Atomic collisions are ideally suited this purpose because the underlying interactions are completely understood, while particle numbers can be small enough to make detailed complete measurements. In one aspect of this work, "kinematically complete" studies of ionizing collisions is studied by measuring the recoil momenta of all particles after a collision using a Cold Target Recoil Ion Mass Spectrometer (COLTRIMS). The PIs plan to study proton-hydrogen (p-H) collisions to provide stringent tests of three-body dynamics theories and then continue to hydrogen-hydrogen and proton-helium collision measurements (two different types of four-body systems). The goal of these experiments is to explore the correlation between the electrons and how this influences the collision. Another aspect of this work involves measuring and comparing electron and positron (anti-electron) impact ionization in far greater detail than previously possible. The goal here is to investigate differences which occur simply because the charge of one of particles is altered from positive to negative. In addition, these studies enhance our understanding of how antimatter interacts with matter.
The broader impact of this work is in the areas of education of graduate students, undergraduates, and high-school students. In addition, understanding of few-body dynamics that come from these experiments will have an impact on other areas of physics where the underlying forces are not well understood.
