A study of equilibrium in argon arcs

Abstract

The intensities of the 7147 Å Ar i and 4806 Å Ar ii lines obtained from wall-stabilized arcs at pressures of 0.2 to 5 atm are presented in an Olsen-Richter diagram. Departures from equilibrium are evident at electron densities below 5 × 10¹⁶ cm^-3. The assumption of equilibrium at higher electron densities leads to transition probabilities in fair agreement with lifetime measurements.