Energy transfer between helium metastable particles and neon

Light absorption and emission spectroscopy was used to study the time dependences of the Hem(2S3), He2m(a u+3), and Nem(P23) number densities and spectral-line emission intensities from 19 NeI states during the afterglow of helium-neon discharges. The NeI states below 20.56 eV are produced, either directly or by cascading, by excitation transfer between Hem(2 S3) and Ne with a reaction rate constant of 4.3×10-12 cm3s-1, in agreement with previous studies. The Ne(2p53s) states are formed directly by the dissociative- excitation-transfer mechanism He2m(a u+3)+Ne→(He2Ne)r*→Ne(2p53s) +2He involving an intermediate repulsive state. No evidence was found for the production of NeI energy levels above 20.56 eV by binary energy-transfer processes.