Kinematically Complete Measurements for Positron Impact Ionization of Atoms and Simple Molecules

University Of North Texas, Denton TX

Investigators

Abstract

This project comprises an international collaboration to address precision measurements of fundamental interactions between antimatter and matter. Positrons (sometimes referred to as the anti-particle of the electron), impinging upon atoms and simple molecules, provide a unique opportunity to study the fundamental physics of these interactions. We measure the initial and final state momentum of each of the particles in a kinematically complete experiment. This provides the most stringent of criteria for comparing experiment with theory, and for studying the physics of highly correlated systems. In the case of simple molecules, it also enables us to extend the study of interactions to spatially-oriented molecules. The understanding of these interactions is essential to precision modeling of positrons interacting with more complex molecules and may lead to diverse applications such as enhanced resolution for Positron Emission Tomography (PET) scans and the effects of beta decay of radio-isotopes on human tissue. It is a collaborative effort including scientists from the Australian Research Council's Center of Excellence for Antimatter-Matter Studies (CAMS) headquartered at the Australian National University and the Max-Planck-Institüt fur Kernphysik in Heidelberg. This research includes post-doctoral researchers and graduate and undergraduate students in an international "one-world" environment. As is often the case for these laboratory scale experiments, the students and post-docs are involved in all aspects of the research, from conception and development of the experimental apparatus through to the operation and diagnosis of the experiments, and analysis and publication of results.