Fluorescence efficiencies of nitrogen and air excited by neon and sodium ions at 0.3–2.0 MeV

Abstract

The fluorescence efficiencies for excitation of nitrogen and air by neon and sodium ions have been measured at bombarding energies between 0.3 and 2.0 MeV. The molecular spectra studied were the first negative system of N2+ (1N) and the second positive system of N2 (2P). The atomic spectra studied were the N+ 5003 Å multiplet and the N+ 5680 Å multiplet. The fluorescence efficiencies of the 3914 Å band and the 4278 Å band of the 1N system and the 3371 Å band of the 2P system were derived directly from the fluorescence data as were the efficiencies of the 5003 Å and 5680 Å multiplets. Efficiencies relative to the 3914 Å band were estimated for the (ν′ = 0, ν″ = 0–3) bands of the 1N system and the (ν′ = 0, ν″ = 0–5), (ν′ = 1, ν″ = 0–6), and (ν′ = 2, ν″ = 2–7) bands of the 2P system. In addition, collisional deactivation coefficients for the 5003 A and 5680 A multiplets were derived from the efficiency data. The efficiencies of all spectra studied increased with increasing energy, with the efficiency of the 3914 Å band being the largest (0.48%) at 2.0 MeV for Ne+ in N2. The ratio of the intensity of the 4278 Å band to that of the 3914 Å band indicates that the Franck-Condon principle is obeyed in this particular case. Also, the ranges of neon and sodium in nitrogen and air were obtained from emission measurements.