Abstract: The evolution of plasma environments is defined and governed by balances between ionizing processes, chemical rearrangements, and neutralisation reactions such as mutual neutralisation (MN). Measuring and explaining these processes in detail is fundamental to understanding and modelling non-local thermal equilibrium environments, such as atmospheric plasmas.
Until recently, experimental studies of MN involving molecular ions in flow tubes and merged-beams were limited to measurements of overall reactivities without information of the mechanism or the products. The cryogenic Double ElectroStatic Ion Ring ExpEriment facility makes such studies possible.
Here, it is possible to control and manipulate the internal energies of the ions, fine-tuned their collision energy, and identify the reaction products and the states they are in. This opens possibilities to reach new insights on balances between different MN reaction pathways and their dynamics, and here I focus on MN relevant to atmospheric phenomenon such as sprites: investigating reactions involving molecular oxygen and nitrogen ions, I probe competition between product channels and unravel effects of internal energy in the molecular ion on the reaction.