A Neutron Spectra Unfolding Code, Based on Iterative Procedures, Designed under LabVIEW Environment

The measurements of the neutron spectrum with the Bonner Spheres Spectrometer system for radiation protection porpoises is an ill-conditioned problem having an infinite number of solutions, therefore, the determination of neutron spectrum is a not a trivial problem because the unknown is not given directly as a result of the Bonner spheres measurements. The current interest in the neutron spectrum unfolding problem has stimulated the development of diverse procedures which try to obtain a better energy resolution through the unfolding of the spectrum. During the past decades, several codes based on iterative, parametric and maximum entropy procedures have been developed like BUNKIUT, BUMS, FRUIT, UMG, etc., to attain improved energy resolution through spectrum unfolding. However, these methods still present some drawbacks such as the complexity in their use, the necessity of a very expert user and an initial guess spectrum to initiate the unfolding. The appropriate selection of the initial spectrum affects in great measure the quality of the obtained solution, however, in the practice, this selection is a difficult task. Each of the mentioned difficulties has motivated the development of alternative techniques to solve the problems before mentioned. The aim of the present work was to design a neutron spectra unfolding code called "Neutron Spectrometry and Dosimetry from the Universidad Autnoma de Zacatecas" (NSDUAZ) based on the iterative algorithm known as SPUNIT. This code was designed in a graphical user interface under the LabVIEW programming environment, is friendly to the end user and has a programming routine which automatically selects the initial guess spectrum by using a set of neutron spectra compiled by the International Atomic Energy Agency (IAEA).