Grant: Discovery Grants Program - Individual

The proposed experimental research is in the area of atomic, molecular and optical physics. The absorption of ultra-violet and x-ray radiation results in molecular ionization and fragmentation. These processes are not only important for atmospheric photochemistry and radiation damage, but are also technologically relevant in, for example, plasma etching of silicon and light generation industries. Our proposed molecular breakup studies will be undertaken using intense, polarized light from modern synchrotrons (including the Canadian Light Source in Saskatoon) using momentum imaging methods, and other modern detection techniques, to 'photograph' the charge particles as they explode apart following photoabsorption. It remains a theoretical challenge to understand how the complex motion of the ejected particles is inter-correlated and described by quantum mechanics as well as long range electrostatic forces. We will focus on studying photodouble ionization in small atmospheric molecules using linearly and circularly polarized light. The ""Electron Recycling System"" (ERS) is an international collaboration with scientists in Australia and Britain. The prototype has been constructed in Windsor and recently demonstrated to work. The ERS was conceived as a gas phase electron spectrometer with the aim of performing ultra-high energy resolution low energy electron scattering studies. Such studies are important because electron-molecule collisions create the energetic species that drive chemical and physical changes of matter in environments that range from plasmas to living tissue. Our revolutionary ""race-track"" design is likely to be useful for all types of charged particles e.g. positrons and ions, and offers the potential for not just ultra-high energy resolution beam production but also for storage of charged particles in which the conventional source strength is weak. The prototype ERS will be initially used to perform basic science experiments on temporary negative ion states in atoms and molecules. We will also use it to store ions and perform positron-molecule collision studies.