Application of the different deconvolution methods to the neutron spectrum reconstruction from activation measurement

Abstract

The neutron activation method provides information about the total neutron emission, yet in many applications, the energy distribution of the produced particles is also required. In this paper, codes based on the methods popular in tomography (Tikhonov Regularization, Minimum Fisher Information, Maximum Entropy and Maximum Likelihood Methods) have been developed for the reconstruction of the energy spectra of neutrons emitted by a Gas-Plasma Target Neutron Generator manufactured by a Gradel-Fusion Company. To perform the measurements by the neutron activation analysis the following samples were selected: Al, Zn, Fe, Ni, Zr and Au. Before the analysis of the experimental results, the codes were tested with synthetic data. The correlation between the reconstruction error and the FISPACT-II inventory code simulation's agreement with the measurement data have been determined. The spectrum was reconstructed by all methods separately, and the final result was defined as a mean value of them. The uncertainty of the reconstructed neutron spectra for the activities with an error higher than 10% has been estimated at the level of 22%.