OPTICAL NITROGEN-15 ANALYSIS OF SMALL NITROGEN SAMPLES WITH A MIXTURE OF HELIUM AND XENON TO SUSTAIN DISCHARGE IN AN ELECTRODELESS TUBE

A spectrographic technique has been developed for the determination of the nitrogen-15 abundance, with a mixture of rare gases, helium, and xenon, to sustain the nitrogen discharge. The average natural abundance obtained with 0.2-μg samples of nitrogen was 0.370±0.005 at-%. Preliminary work indicates that this method is applicable directly to plant and liquid samples. © 1968.