Feasibility study of a coded aperture imaging technique for position-sensitive muonic X-ray atomic ratio reconstruction

Abstract

A position-sensitive multi-compound inspection methodology using Muonic X-ray Emission Spectroscopic (μ-XES) element analysis is proposed due to the ability of the coded aperture imaging technique to maintain the relative intensity of X-rays. This methodology can simultaneously obtain the atomic ratio of different regions of the sample under study. Therefore, the mis-judgements of material compositions caused by averaging results can be reduced. The atomic ratio reconstruction quality is mainly related to X-ray counts (Nx ), atomic ratios of materials (AT ), size and placement of sample blocks. In this work, several different sample blocks made of light elements were designed by GEANT4 Monte Carlo (MC) simulations to study the influences of Nx , AT , size and placement of sample on atomic ratio reconstruction quality. In the inspection of multiple sample blocks, this methodology successfully distinguished the material compositions from different regions by reconstructing the atomic ratios of C/N and O/N. Moreover, this methodology can clearly image element blocks larger than 2 × 2 mm2.