Year
2019
Abstract
In this work a genetic algorithm is used to determine the neutron energy flux spectra of a nuclide source from a scintillation detector output. The neutron spectrum reconstructed in such a way can be used as a tool to identify and characterize neutron sources. Many existing spectrum reconstruction codes today require an a priori approximation of the neutron flux to operate. For the method developed here various existing measurements are incorporated into the algorithm in order to lessen the required knowledge of the source in question and guide the reconstructed spectra towards one that is physically realizable. The detector is modeled using a response matrix generated by MCNPX-POLIMI, which is then verified experimentally. The algorithm is then applied to a a variety of known sources to reconstruct their flux spectra. The reconstructed spectra is then compared against reference spectra, and errors quantified. In addition the effects of modifications to the genetic algorithm in use, such as alterations to the mating method, fitness function, mutation rate, and selection biasing, are explored and presented.