Doubly charged ions in decaying plasmas in neon and argon

Abstract

Doubly charged ions were observed during the decay period of plasmas produced in neon as well as in argon at reduced gas pressures ranging from 0.14 to 1 Torr. The measured time dependence of both the Ne²⁺ ion density and the Ar²⁺ ion density were corrected for the effect of diffusion cooling of the electrons. The reaction rate constant for the partial charge exchange reaction Ne²⁺+Ne→Ne⁺+Ne⁺ was found to be k=(9 ± 2) × 10⁻¹⁴ cm³ sec⁻¹. For the reaction rate of the similar reaction in argon, only an upper limit could be obtained. The value of the mobility of Ne²⁺ in neon was found to be μ(Ne²⁺)=6 ± 1 cm²/V sec. The value of the mobility of Ar²⁺ in argon was consistent with previously published data.