Copper benchmark experiment at the Frascati Neutron Generator for nuclear data validation

Abstract

A neutronics benchmark experiment on a pure Copper block (dimensions 60×70×60cm3), aimed at testing and validating the recent nuclear data libraries for fusion applications, was performed at the 14-MeV Frascati Neutron Generator (FNG) as part of a F4E specific grant (F4E_FPA-395_01) assigned to the European Consortium on Nuclear Data and Experimental Techniques. The relevant neutronics quantities (e.g., reaction rates, neutron flux spectra, doses, etc.) were measured using different experimental techniques and the results were compared to the calculated quantities using fusion relevant nuclear data libraries.This paper focuses on the analyses carried-out by ENEA through the activation foils techniques. 197Au(n,γ)198Au, 186W(n,γ)187W, 115In(n,n′)115In, 58Ni(n,p)58Co, 27Al(n,α)24Na, 93Nb(n,2n)92Nbm activation reactions were used. The foils were placed at eight different positions along the Cu block and irradiated with 14MeV neutrons. Activation measurements were performed by means of High Purity Germanium (HPGe) detector. Detailed simulation of the experiment was carried-out using MCNP5 Monte Carlo code and the European JEFF-3.1.1 and 3.2 nuclear cross-sections data files for neutron transport and IRDFF_v1.05 library for the reaction rates in activation foils. The calculated reaction rates (C) were compared to the experimental quantities (E) and the C/E ratio with relative uncertainties was assessed.