Stepwise Fluorescence in Mercury-Nitrogen Mixtures The 3650 Line

Abstract

The experiments of Wood and of Gaviola show that when mercury vapor is illuminated by light from a mercury arc, and nitrogen is added in increasing amounts, the concentration of atoms in the $^{3}P_{2}$ state passes through a minimum. No simple theory accounts for this result. An explanation involving excitation of atoms in the $^{3}P_{1}$ state by vibrating nitrogen molecules is discussed. The results obtained when a filter of bromine vapor is used indicate a transfer of excited mercury atoms from one to another $^{3}D$ state upon collision with nitrogen.