An attempt to detect stable N- ions from a sputter ion source and some implications of the results for the design of tandems for ultra-sensitive carbon analysis

Abstract

The present paper discusses an experiment, using a Middleton sputter ion source, where a sensitive search was made for 14N- ions in the presence of an intense carbon beam. It was found that negative nitrogen ions, capable of withstanding acceleration fields of 1.5 MV/m, were not produced in detectable intensities. The paper also points out some design requirements of tandem facilities that must be satisfied if full advantage is to be taken of this negative result to permit the measurement of very weak 14C beams