Adam Light: Tabletop plasma physics at Colorado College (CIPS seminar 2023/12/04) скачать в хорошем качестве

Adam Light: Tabletop plasma physics at Colorado College (CIPS seminar 2023/12/04)

Adam Light, Colorado College Tabletop Plasma Physics at Colorado College Research at an all-undergraduate institution presents unique challenges and opportunities. We often prioritize breadth and student agency, which leads to programs with a wide variety of projects. In this talk, I'll give an overview of our work in the Light Lab and highlight two very different, ongoing undergraduate research projects: (1) Non-equilibrium atmospheric pressure plasma typically operates in a regime where electrons have a few eV of energy while ions and neutrals are close to room temperature. These discharges can drive energetic chemical processes efficiently but are difficult to diagnose, particularly at the highly-complex plasma/liquid interface. Lone electrons dissolved in the liquid (“solvated electrons”) are thought to be potent contributors to plasma/liquid chemistry but have not been satisfactorily diagnosed. We are developing a supercontinuum transient absorption spectroscopy system to measure the time-dependent concentration of solvated electrons produced by the plasma at the liquid surface. I will describe our system and current status. (2) In collaboration with the Swarthmore Spheromak Experiment, we are studying particle confinement in elongated force-free magnetic fields. The field structure is very well described by ideal MHD, but the particle orbits are large compared to the gradient scale lengths of the field. Based on this intriguing contrast, we explore particle confinement using numerical simulation. We construct minimum-energy solutions for the force-free eigenvalue equation using the PSI-Tet solver (now part of the OpenFUSIONToolkit) and integrate the proton equations of motion using a Boris stepper. Using a large ensemble of initial conditions, we characterize confinement statistics and orbit properties. I’ll present several interesting puzzles that we are working to understand.