Ultracold neutral plasmas bridge traditional boundaries between atomic physics and plasma physics and between atomic physics and condensed matter physics. This experimental research program focuses on probing the early-time non-equilibrium dynamics of ultracold neutral plasmas, at times short compared to the inverse electron and ion plasma frequencies. It is only during this time that both the ions and the electrons are strongly coupled. This coupling fundamentally changes the ion-ion and electron-ion interactions. The project will include the first direct measurements of the three-body recombination rate in this regime. Theoretical predictions of the rate are uncertain by at least an order of magnitude, and the exact scaling with temperature and density is unknown. The groups high-sensitivity, high-resolution fluorescence techniques enable measurement of small changes in the ion system that arise from interactions with the electrons. The broader impact of the program centers on a heavy involvement of undergraduates as well as outreach to high school science teachers.
