RUI: Low Energy Electron Scattering from Fundamental Molecular and Atomic Targets

Csu Fullerton Auxiliary Services Corporation, Fullerton CA

Investigators

Abstract

The project involves experiments to study how low energy electrons collide with atomic or molecular gases, undertaken in collaboration with theoretical physicists. The studies will help elucidate the basic physics of collisions as well as have applications in ozone chemistry, combustion, the microelectronics industry, and astrophysics (from observations of light emitted in electron collisions with atoms and molecules in space). The project heavily involves undergraduate and high school students from underrepresented groups in a region of the country which has predominantly Hispanic and other minority students. The students are mentored to learn hands-on broad experimental science laboratory skills and go on to further education towards a Masters or PhD. In the past 26 years, the project has involved about 120 undergraduate students. In 2005, the PI was given a prestigious National Award for Outstanding Research in an Undergraduate Institution "For his challenging and sophisticated experiments in electron-atom collisions that have provided significant tests of atomic theory and for his energetic, sustained mentoring of students in his research." The focus of the project is to obtain scattering cross sections for electron scattering from fundamental atomic and molecular gaseous targets, for elastic electron scattering and for excitation and ionization of these targets at very low energies (around 1eV to 100eV), including energies well above the ionization energy of these targets. Recently, to complement their differential-angle, high-resolution, low energy electrostatic electron spectrometer, the laboratory (PI and undergraduate students) designed and built a differential-angle time-of flight electron spectrometer, which is uniquely suited to study very low energy electron collisions. This is presently the only system existing world-wide. In 2018-2019 it provided benchmark collision data for molecular hydrogen to test the theoretical work from Curtin University and Los Alamos National Laboratory. The two lab spectrometers continue to be deployed to study other fundamental targets such as carbon monoxide and water. The PI collaborates with leading groups in theoretical modeling of electron scattering, e.g. at Los Alamos National Laboratory in USA, Drake University in Iowa USA, Curtin University in Australia, Charles University in Prague, University College in London UK, and several theory and experimental groups in Brazil, Canada and India. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.