Laser Optogalvanic Study of a Helium Hollow Cathode Discharge

Abstract

A helium hollow cathode lamp operated under flow conditions provides a simple optogalvanic source with typically large voltage transients. An analysis of the transients for the two transitions at 3889 Å and 5015 Å using a simple two-level kinetic model suggests that the upper states of these transitions (33 P and 31 P, respectively) are quite different in their sensitivity to lamp pressure. Reasons for the variations observed in the transients with varying pressure and applied voltage are discussed.