Beginning of Muon Scattering Tomography - Portal Scanner

High-Z material can be detected and located in three dimensions using radiographs formed by cosmic-ray muons. The detection of these materials hidden inside large volumes of ordinary cargo is an important and timely task given the danger associated with illegal transport of uranium and heavier elements. Existing radiography techniques are inefficient for shielded material, are often expensive and involve radiation hazards, such as gamma rays and X-rays.

Muon scattering tomography utilizes Coulomb scattering of muons and two detection systems with a test subject placed in between to produce a 3D density distribution model of the analysed volume. This technique was developed by Los Alamos National Laboratory (LANL) as a way to detect nuclear smuggling.

Borozdin et al. (2003) demonstrated that compact high-Z objects can be detected and located in three dimensions with muon radiography. A portal scanner based in muon tracking technology was installed in the Freeport, Bahamas, and can detect both shielded nuclear material, as well as explosives and contraband. The scanner is large enough for a cargo container to pass through. It then produces a 3-D image of what is scanned (Patnaik et al., 2014). A recent study published by Antonuccio et al. (2017) shows how such a portal works and how one will be built.

Publications:

"Detection of high-Z objects using multiple scattering of cosmic ray muons" (Borozdin et al., 2003)

"Image Based Object Identification in Muon Tomography" (Patnaik et al., 2014)

"The Muon Portal Project: Design and construction of a scanning portal based on muon tomography" (Antonuccio et al., 2017)