Towards a muon scattering tomography system for both low-Z and high-Z materials

Abstract

Muon scattering tomography (MST) is a non-destructive technique to image various materials by utilizing cosmic ray muons as probes. A typical MST system with a two-fold track detectors is particularly effective in detecting high-Z materials (e.g. nuclear materials), but difficult to recognize low-Z materials (e.g. explosive materials). In this work, we present a concept of MST system to discriminate both low-Z and high-Z materials by extra measuring momentum of low-energy muons with a Cherenkov detector. A toy Monte Carlo simulation to describe detector responses and multiple scatterings of a muon tracking through materials is developed for statistical tests. Based on momentum-dependent track reconstruction and image reconstruction algorithm, we evaluate separation powers of different materials in the system. The results show that momentum measurement of low-energy muons and accurate track reconstruction can improve separation power of low-Z materials significantly. This may enable the MST system to detect both low-Z and high-Z materials with cosmic ray muons in the whole energy range.

Automated object detection for muon tomography data analysis

“…Cosmic-ray muons have energies at sea level about 3-4 GeV and are able to penetrate much deeper into the materials compared to X-rays. Cosmic-ray tomography (CRT) [1][2][3][4][5][6] is considered to be a new inspection technology, complementary to the X-ray imaging which is most widely used to scan cargo at borders. It is expected that CRT will help to increase the number and fraction of scanned cargoes.…”

Geant4 simulation study of low-Z material detection using muon tomography

“…It is expected that CRT will help to increase the number and fraction of scanned cargoes. Besides detection of high atomic number materials, namely Special Nuclear Materials there was research on possibility to detect low-Z materials [4][5][6].…”