Energetic charged particles precipitating into the earth's atmosphere cause atmospheric heating, ionization and optical emissions. The understanding of these effects requires the knowledge of the ability of the various atmospheric constituents to react to these particles. The measurement of this ability to transfer energy is done in laboratory cross-section experiments. The work proposed here focuses on the accurate measurement of absolute cross-sections which can be applied directly in theoretical models that predict the aeronomic consequence of particle precipitation. This research centers on collision in atmospherically relevant species, specially including the atomic oxygen atom. New techniques will be implemented for mass spectrometry, measurement of large scale scattering, production of O-atom scattering targets and study of dissociative excitation.
