Spectroscopic radiography with monoenergetic neutrons for homeland security applications

Abstract

In this thesis, I discuss the hypothesis, testing, and applications of a radiographic system which uses the spectral analysis of fast neutrons generated in the 11B(d,n[gamma])12C reaction. Neutron radiography in current use systems employs a total count analysis to reconstruct hydrogenous content in scanned cargoes. This research presents a technique which leverages the large differences in the energy dependence of neutron interaction cross sections between hydrogenous materials and those of higher atomic number. These dependencies result in characteristic spectral details of hydrogenous materials which may be analyzed to classify type and areal density of cargo contents. The studies presented here demonstrate that this technique is feasible and suited to the application of national security port monitoring at industry-requisite speeds and cargo dimensions.