Electron impact processes in nitrogen rich atmospheres of the outer solar system

Electron collisions with N₂ are predominant components of the interaction between outer solar-system atmospheres and solar photons, solar wind, and magnetospheric electrons. Our collaboration between the Jet Propulsion Laboratory (JPL) and the California State University, Fullerton (CSUF), has devoted a significant effort over the last few years to improving the knowledge base of electron-N₂ excitation phenomena. Here, we highlight the lack of Franck-Condon behaviour in excitation of the Rydberg-valence states, using excitation of the C³Π_u state as a case in point. Further, we briefly introduce ongoing work measuring vibrationally-resolved emission cross sections for the Lyman-Birge-Hopfield (LBH) band system of the a¹Π_g (v') → X¹Σ⁺_g (v'') transitions. Specifically, we present preliminary results for the relative (3,0) emission cross section, which calls the currently accepted LBH shape function of Ajello and Shemansky (1985 J. Geophys. Res.-Space 90 9845) into question.