Strong field studies of F$_2^-$ dissociation and photodetachment*

While molecular anions have long been used as tools to investigate molecular dynamics, very few studies focus on their behavior in a strong field. In this work, we explore the strong field dissociation and photodetachment of F$_2^-$ under a variety of laser conditions. The use of a keV beam of F$_2^-$ allows us to measure all of the molecular fragments except electrons, and we obtain the full 3D momentum of breakup using a coincidence 3D momentum imaging technique. Past measurements of photoelectrons from F$_2^-$ resulted in some uncertainty about the photoemission mechanisms due to unknown nuclear dynamics$^1$. Our measurements of the final nuclear products (both F$_2$ and F + F) help clarify the underlying physics associated with this previous study. In addition, we identify dissociation pathways and use the measured kinetic energy release (KER) to evaluate the initial rovibrational population of the anion. \\ $^1$ Hannes Hultgren and Igor Yu. Kiyan, Phys. Rev. A \textbf{84}, 015401 (2011). \\ * This work was supported by the Chemical Sciences, Geosciences, and Biosciences Division, Office of Basic Energy Sciences, Office of Science, U.S. Department of Energy.