THE QUALITY-CONTROL IN THE PRODUCTION OF SPIKED REFERENCE MATERIALS FOR GAMMA-RAY SPECTROMETRY

Following a EUROMET project for the development of a range of spiked r eference materials for gamma-ray spectrometry, a number of hew techniq ues were adopted at ENEA for the routine production of these materials . A quality control of the produced samples was simultaneously started . It is based on HPGe gamma-ray spectrometry of the different samples in Marinelli beaker measuring geometry. Within a few years a great num ber of materials, with density values ranging from 0.4 to 1.8 g cm(-3) and different chemical composition, spiked with mixtures of gamma emi tters (60 to 1836 keV), were processed. The full-energy-peak efficienc y values for the different matrices were normalised to a reference sam ple composition allowing the reduction of the acceptability criteria o n which the quality control is based. Two theoretical models were used to compute the self-attenuation corrections obtaining a satisfactory agreement in the considered range of sample parameters. (C) 1998 Elsev ier Science Ltd. All rights reserved.