Über das Nachleuchten von A, N2 and N2 plus CH4 nach Stoßanregung durch Elektronenlawinen

Abstract

In a pulsed discharge gap the blue and near UV radiation due to exciting impacts caused by electron avalanches is investigated. Cutting-off the gap voltage rapidly stops the avalanche process but not the light emisison which shows an exponential decay, the decaytime τ being pressure dependent (quenching process) . By extrapolation to zero pressure mean lifetimes of the observed excited states are obtained (N2: τ0 = 36 · 10 -9 sec; Ar: τ0Ι= 1,5 · 10-6 sec. τ0III = 2 · 10-8 sec). In Argon yet another state (II) is detected which filles up the lower radiating state (Ι) (τ0ΙΙ=0,7 · 10-6 sec). The excitation of state (II) is favoured by raising E/p of the preceding avalanche discharge.Quenching in Argon is insignificant (quenching probability w′ < 10-3) while in Nitrogen we obtain w′ ≈ 5 · 10-2 from the measured quenching pressure p′= 58 Torr. The N2 radiation is very much effected by addition of Methane: Practically every impact with a Methane molecule leads to quenching of the excited N2 molecules.