Imaging of high-Z material for nuclear contraband detection with a minimal prototype of a Muon Tomography station based on GEM detectors

TL;DR

This paper demonstrates a prototype Muon Tomography station using GEM detectors to effectively detect and image small high-Z and medium-Z materials, advancing non-invasive nuclear contraband detection techniques.

Contribution

The study presents the first successful detection and imaging of small high-Z and medium-Z targets using a GEM-based Muon Tomography prototype.

Findings

Successful detection of small high-Z targets (~0.03 liters)

Effective imaging of medium-Z and high-Z materials

Prototype demonstrates potential for nuclear contraband detection

Abstract

Muon Tomography based on the measurement of multiple scattering of atmospheric cosmic ray muons in matter is a promising technique for detecting heavily shielded high-Z radioactive materials (U, Pu) in cargo or vehicles. The technique uses the deflection of cosmic ray muons in matter to perform tomographic imaging of high-Z material inside a probed volume. A Muon Tomography Station (MTS) requires position-sensitive detectors with high spatial resolution for optimal tracking of incoming and outgoing cosmic ray muons. Micro Pattern Gaseous Detector (MPGD) technologies such as Gas Electron Multiplier (GEM) detectors are excellent candidates for this application. We have built and operated a minimal MTS prototype based on 30cm \times 30cm GEM detectors for probing targets with various Z values inside the MTS volume. We report the first successful detection and imaging of medium-Z and high-Z targets of small volumes (~0.03 liters) using GEM-based Muon Tomography.