The Influence of Argon, Helium, Oxygen, and Carbon Dioxide on Emission Spectra in the DC Arc*

Abstract

A gas-tight arc stand has been constructed to study the influence of A, He, O2, CO2, and various mixtures of these gases on emission spectra produced in the d.c. arc. The band spectra of CN are replaced and it is found that in most lines studied the signal-to-noise ratio is better in A and He than in Air. A 2 to 100-fold increase in the signal to noise ratio has been observed. It is suggested that this technique may prove useful in spectrochemistry.