A hybrid radioassay technique for multiple beta-emitter mixtures using liquid and NaI(Tl) scintillation spectrometers

Multiple pure-beta and beta-gamma emitter mixtures can be reliably radioass ayed using a combination of a liquid and a NaI(TI) scintillation spectromet er. The method of least squares has been applied to the radioassay of relat ively low-activity samples. This system removes the difficulty of analysing beta-emitter mixtures with very similar liquid scintillation pulse height distributions, such as H-3, Cr-51 and I-125. All that is required for the t echnique is a quenched standard sample set of the nuclides to be analyzed a nd calibration standard samples for the gamma-emitters. (C) 1999 Elsevier S cience Ltd. All rights reserved.