GEANT4 Simulation of a Cosmic Ray Muon Tomography System with Micro-Pattern Gas Detectors for the Detection of High-Z Materials

TL;DR

This paper presents a detailed GEANT4 simulation of a muon tomography system using micro-pattern gas detectors, demonstrating its effectiveness in detecting high-Z materials within cargo containers through 3D imaging.

Contribution

It introduces a novel simulation framework for GEM-based muon tomography, assessing detection capabilities and effects of various parameters for threat material identification.

Findings

GEM detectors enable high-resolution muon tracking for tomography.

The system effectively discriminates high-Z materials in simulated scenarios.

Placement and shielding influence detection accuracy.

Abstract

Muon Tomography (MT) based on the measurement of multiple scattering of atmospheric cosmic ray muons traversing shipping containers is a promising candidate for identifying threatening high-Z materials. Since position-sensitive detectors with high spatial resolution should be particularly suited for tracking muons in an MT application, we propose to use compact micro-pattern gas detectors, such as Gas Electron Multipliers (GEMs), for muon tomography. We present a detailed GEANT4 simulation of a GEM-based MT station for various scenarios of threat material detection. Cosmic ray muon tracks crossing the material are reconstructed with a Point-Of-Closest-Approach algorithm to form 3D tomographic images of the target material. We investigate acceptance, Z-discrimination capability, effects of placement of high-Z material and shielding materials inside the cargo, and detector resolution effects for such a MT station.