Abstract

Twenty-four samples of CO 2 from combustion of the NBS oxalic-acid radiocarbon standard, submitted from 13 radiocarbon laboratories, were analyzed for C 13 content in this laboratory in order to provide comparative data for normalizing the counting results. The samples were analyzed on Samson, a 60° sector, six-inch radius, McKinney-Nier type mass-spectrometer with magnetic switching between sample and standard gas feed to the instrument.