2022/01/06 by Ahmad Alrheli, D. Barker, Alrheli, A. F. +17
Earth and Planetary Sciences · Physics and Astronomy · #Data Analysis #FOS: Physical sciences #Geophysical and Geoelectrical Methods #High Energy Physics - Experiment (hep-ex) #Instrumentation and Detectors (physics.ins-det) #Particle Detector Development and Performance #Radiation Detection and Scintillator Technologies #Statistics and Probability (physics.data-an)
paper · pdf · doi:10.48550/arxiv.2201.01877
openalex publication_date 2022/01/06 · openalex created_date 2022/04/03 · openalex updated_date 2026/07/28
Muon Scattering Tomography (MST) has been shown to be a powerful technique for the non-invasive imaging of high-shielded objects. We present here the application of the MST technique to investigate two types of nuclear waste packages, a small-steel drum and a large nuclear waste cask, namely, a CASTOR V/52. We have developed a quantitative method using the contrast-to-noise ratio (CNR) to evaluate the performance of an MST detector system in differentiating between high-, medium-, and low-Z materials inside nuclear waste packages with different shielding types. This study reveals that our MST detector system is able to differentiate between a (10 × 10 × 10 cm3) uranium cube, embedded within a concrete matrix inside the small-steel drum, and regions of background signal in six hours of muon exposure time with a CNR value of 3.1±0.2. During our investigation of the highly-shielded cask, the reconstructed images of the cask contents indicated the ability of our system to detect irregular baskets, such as empty baskets, with a CNR value of 5.0±0.3 after 30 days of muon exposure. These studies were done using a Monte Carlo simulation tuned to the performance of resistive plate chambers (RPCs) based muon tomography system built by the University of Bristol, which had a reported position resolution of 350 micron. Here we also report the dependence of the performance on the position resolution. We argue that using a combination of RPC and drift chambers (DC) detectors with 700 micron and 4 mm position resolutions respectively is able to generate tomographic images of well-shielded materials in a few hours of muon exposure time. With these position resolutions, our system needs six hours of muon exposure time to produce a good quality image of a cube of uranium with side-length of 10 cm shielded by a concrete matrix with CNR value of 2.4±0.25.