NEANDC Working Group on Activation Cross Sections

Abstract

On recommendation of the Nuclear Energy Agency (NEANDC) an international working group on activation cross-sections was formed in 1989, which, at its first meeting, initiated an intercomparison of activation cross-section measurements using the D(d,n)³He and H(t,n)³He reactions. For this purpose excitation functions for the ⁵⁸Ni(n,p)⁵⁸Co and ⁹³Nb(n,2n)^92mNb reactions have been measured at the Argonne National Laboratory and the Physikalisch-Technische Bundesanstalt, Braunschweig (PTB) using neutrons produced by means of the D(d,n)³He reaction and in a collaboration Los Alamos National Laboratory — Institut für Radiumforschung, Vienna (IRK) by means of neutrons produced by the H(t,n)³He reaction in order to test the different corrections needed to account for the deficiencies of the respective source reactions. Measurements at Argonne were performed in the neutron energy range Eⁿ = 5–10 MeV, at PTB in the range Eⁿ = 8–14 MeV and at Los Alamos for 5–13 MeV neutrons. Reasonable agreement was obtained between the results of the three groups for most of the investigated neutron energy range, there are however also some small discrepancies, both in the gamma-efficiency calibration and some cross-section values which need further study. The data obtained in this intercomparison substantially improve our knowledge on the excitation function of the two important dosimetry reactions.