Determination of Ionization Cross Section for Argon Metastable-Metastable Collision by Means of Afterglow Technique

Subtracting the energy loss rates of electrons from the decay rate of electron temperature in an argon afterglow at pressure 133 Pa (Ar), we have separated the energy gain of electrons, which was assumed to be due to superelastic collisions and energetic electrons created by the metastable-metastable ionizing collisions. The cross section obtained has a value between (1.30±0.11)×10-17 m2 and (1.40±0.12)×10-17 m2, which is greater than the cross section for collisions between unexcited argon atoms.