Fluorescence from Electron Irradiated Gases in Refurbished LABCEDE.

Abstract : This report describes our efforts directed toward the study of electron-irradiated gases of atmospheric interest as part of the LACEDE project. Emission spectra of nitrogen and air between 185 and 900 nm were surveyed and compared to observations of auroral radiances. Infrared spectral surveys using a CVF and interferometer provided many intriguing observations which suggest numerous future measurements programs. A series of measurements undertaken on the higher-pressure apparatus identified N(2D) as responsible for NH formation in N2/H2 mixtures by altering the neutral and ionic kinetics with trace species. The absolute production rates of vibrationally excited NO in irradiated N2/O2 mixtures are determined, with N(2D) felt to be the reaction precursor. About two precent of the total energy deposited in the gas by the electron beam appears as NO vibrational energy, A discussion of self-trapping of CO2(nu5) emission is given to illustrate the modification of the observed fluorescence spectrum due to 'hot band' and istopic emissions. The excitation and quenching of Meinel bands by air and nitrogen are also reported. Large intensity enhancements have been observed in the presence of applied magnetic fields. Preliminary observations and explanations of this beam plasma discharge phenomenon are given. Keywords: Electron irradiation; Fluorescence; cryogenic; Interferometry; Circularly variable filters; Photometers; Electron beam; Nitrogen Oxide; Carbon dioxide; Beam plasma discharge; Quenching; ozone; Production efficiencies; Magnetic fields; Nitrogen; Oxygen; Hydrogen.