Electron- and Photon-Induced Dynamics

University Of California-Davis, Davis CA

Investigators

Abstract

Modern experimental techniques such as COLTRIMS (cold target recoil ion momentum spectroscopy) sometimes referred to as a 'reaction microscope', allow detailed measurements of the dynamics of the reaction. It is now possible to record in coincidence, both photoelectron angular distributions and the momenta of all charged molecular fragments. These studies are an excellent probe of the dynamics in the interaction of photons and electrons with molecules and the subsequent flow of energy between the vibrational modes of the system. These measurements pose a new challenge to theoretical predictions, but also an opportunity to understand these processes. This research program will study electron scattering from molecules and molecular ions and the subsequent dynamics following the collision. The calculations produce accurate and reliable cross sections, resonance parameters, and can describe in detail the nuclear dynamics following the electron collision. The systems that will be studied range from studies of dissociative recombination, which are critical in understanding the formation of molecules in interstellar clouds, dissociative excitation, which is important in low-temperature plasmas, such as combustion flames and the study of photoionization of polyatomic systems - predicting angular distributions from fxed-in-space molecules. All of this leads to a better understanding of these reactions, with an ultimiate goal of controlling the dynamics. This research will enhance infrastructure for research and education. It will be carried out at the Department of Applied Science, University of California, Davis, a multi disciplinary graduate program that houses faculty and students from a wide range of areas. The PI has strong collaborations with Lawrence Berkeley Lab. In addition, she maintains a strong collaboration with international partners, in particular the experimental effort at the CRYRING in Sweden, the TSR in Germany and with theoreticians at the Universite de Havre, France. Students from both these institutions have made long-term visits to work with the PI. These collaborations are on-going. In addition it will broaden participation of underrepresented groups. As one of the few faculty women in her college (and department), the PI acts as a mentor to new students, particularly women who are entering the program. Women, particularly women who are active in research, constitute one of the presently under represented groups in physics. The PI has and continues to serve as a role model for students. She has been the thesis adviser for several women students. The PI has been involved in classes whose purpose is to reach out to non-science majors on campus and give them some idea of what science is. For the past three years she has taught a Freshman seminar, "How to make a lens" which had a 50/50 enrollment of science vs non-science majors. In Spring 08, she taught an additional Freshman seminar, "How things work". The majority of the students were non-science majors. These seminars were very successful. In particular, the "How things work" was very popular with the students. This year, the PI taught a general education class entitled based on the seminar that was very well-received by the students. These students were mostly freshman and sophomore non-science majors.