Standardisation and measurement of the decay scheme data of Np-237

Within the framework of a EUROMET project, a solution of Np-237/Pa-233 at equilibrium has been standardised by 4 pi(PC)-gamma counting. An intrinsic Ge spectrometer was employed to measure relevant gamma-ray emission probabilities. Good agreement was obtained for those pertaining to the decay of Pa-233, but not for the gamma-ray emissions following the decay of Np-237. The cause of such discrepancies is discussed. Crown Copyright (C) 2000 Published by Elsevier Science Ltd. All rights reserved.