The role of metastable atoms in glow discharge ionization processes

Effect of small quantities of oxygen in a neon glow discharge

“…Solanki et al 14 investigated the excitation of ion laser transitions in noble gas mixtures in hollow cathode discharges and reported that the dominant excitation mechanism of noble-gas ions was found to be collisions of the second kind between the ground-state noble-gas ions and neon metastables. Evidence for the role of Penning ionization in very low current (1-5 mA), low pressure ($1 hPa) glow discharges was provided by Hess and Harrison 15 using neon and argon as discharge gases. Using various models Bogaerts and Gijbels have used a mathematical simulation to compare neon and argon as discharge gases in a dc glow discharge.…”

A laser ablation millisecond-pulsed glow discharge time-of flight mass spectrometer (LA-GD-TOFMS) for quasi-simultaneous elemental and molecular analysis

“…Under GD low-pressure conditions, metastable atoms transfer their energy through inelastic collisions (PI) to analyte atoms for several milliseconds. 25 In case of argon as plasma gas, the energy amounts to $12 eV implying that ions of intact molecules and only a few fragments are formed if the ionization potential of the analyte falls below this value.…”

Laser-scattering instrument for fundamental studies on a glow discharge

“…However, previous studies on argon glow discharges have shown that the argon atom numberdensity is y10 16 and the argon metastable number-density from 10 11 -10 12 cm 23 . 2,26,27 These previous studies were not Fig. 6 ''Linearized'' Thomson-scattering spectrum.…”