Non-intrusive non-destructive method to detect fissile material

The detection of fissile materials is of great interest to the National Homeland Security effort. Significant advantages of a technique using nuclear acoustic resonance (NAR) over the traditional detection methods are that it will not rely on nuclear radiation signatures, will be non-intrusive, and has the potential to identify individual components of composite substances including fractional isotope composition of the material under investigation. Technique uses the unique nuclear acoustic resonance signatures generated when materials are driven by high intensity resonant acoustic waves in the presence of a constant magnetic field. This would cause shifts in the nuclear and electronic spin energy levels of the material. Nuclear energy level shifts induce changes in the unique nuclear magnetic properties of the material which can then be quantified using sensitive instruments. This paper will discuss in detail, the physics and detection principles of NAR and also provide some preliminary results.