A novel reconstruction technique for two-dimensional Bragg scatter imaging

TL;DR

This paper introduces a new reconstruction method for 2D Bragg Scattering Tomography that effectively reduces artifacts using a combination of multibang control and microlocal analysis, validated through Monte Carlo simulations.

Contribution

The paper presents a novel reconstruction technique for BST that combines multibang control and microlocal analysis to regularize artifacts, including boundary and approximation-induced artifacts.

Findings

Effective artifact reduction demonstrated in simulated data

Method applicable to airport baggage screening scenarios

New Monte Carlo code for data simulation and model validation

Abstract

Here we introduce a new reconstruction technique for two-dimensional Bragg Scattering Tomography (BST), based on the Radon transform models of [arXiv preprint, arXiv:2004.10961 (2020)]. Our method uses a combination of ideas from multibang control and microlocal analysis to construct an objective function which can regularize the BST artifacts; specifically the boundary artifacts due to sharp cutoff in sinogram space (as observed in [arXiv preprint, arXiv:2007.00208 (2020)]), and artifacts arising from approximations made in constructing the model used for inversion. We then test our algorithm in a variety of Monte Carlo (MC) simulated examples of practical interest in airport baggage screening and threat detection. The data used in our studies is generated with a novel Monte-Carlo code presented here. The model, which is available from the authors upon request, captures both the Bragg scatter effects described by BST as well as beam attenuation and Compton scatter.