Multiple monoenergetic gamma radiography (MMGR) with a compact superconducting cyclotron

Smuggling of special nuclear materials and nuclear devices through borders and ports of entry constitutes a major risk to global security. Technologies are needed to reliably screen the flow of commerce for the presence of high- Z materials such as uranium and plutonium. Here, we present an experimental proof-of-concept of a technique that uses inelastic ( p , p ') nuclear reactions to generate monoenergetic photons, which provide means to measure the areal density and the effective- Z ( Z eff) of an object with an accuracy surpassing that achieved by current methods. We use an ION-12 SC superconducting 12MeV proton cyclotron to produce 4.4, 6.1, 6.9, and 7.1MeV photons from a variety of nuclear reactions. Using these photons in a transmission mode, we show that we are able to accurately reconstruct the areal densities and Z eff of a test object. This methodology could enable mobile applications to screen commercial cargoes with high material specificity, providing a means of distinguishing common cargo materials from high-Z materials that include uranium and plutonium.