An experimental study of the reactions of excited neon atoms in pure afterglow plasmas using resonance absorption spectrometry

Resonance absorption spectrometry has been applied in a room temperature study of the reactions of excited neon atoms in pure afterglow plasmas. The pressure range 10-500 Torr was investigated. Lorentz broadened linewidths calculated using a simple classical interruption theory allowed fractional absorption signals as large as 98% to be analysed and absolute excited-state concentrations to be determined. The first absorption studies of the decay of 1 P 1 excited atoms in neon afterglows are reported. Analysis of the decay profiles of the 3 P 2 , 3 P 0 and 1 P 1 excited states allowed quenching rate coefficients for each state to be determined and the role of neutral atoms and electrons in the afterglow relaxation to be studied. The importance of charge neutralisation of the dimer ion Ne 2 + as an afterglow source of 1 P 1 excited atoms was established in this study.