In recent years, Muography has been applied in many areas such as geological prospecting and national security. With the development of Muography, the demand for precise algorithms is on the rise. This paper focuses o...
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In recent years, Muography has been applied in many areas such as geological prospecting and national security. With the development of Muography, the demand for precise algorithms is on the rise. This paper focuses on Muon Tomography and proposes a new Muon Tomography algorithm that decomposes muon scattering angles into changes in azimuthal angle phi and polar angle theta in a spherical coordinate system. Calculate their change ratios to determine the equivalent scattering point. This algorithm divides the calculation of muon scattering points into three steps to enhance the equivalent accuracy of the muon trajectories. The new algorithm is applied to process both simulation and experimental data. It combines three methods for evaluating imaging quality: the SSIM(Structural Similarity Index Measure) algorithm, Ratio of Effective Scattering Point, and Spectrum of the Distance from Scattering Points to the Origin. These methods are used to compare the image quality of the new algorithm with the poca algorithm. The results show that compared to the poca algorithm, the new algorithm significantly improves the image quality without angle selection, nearly doubling the fraction of effective scattering points. When imaging low-Z materials where the poca algorithm is not suitable, the new algorithm also effectively enhances the imaging quality. Also, the imaging quality can be further optimized by continuously iterating the boundary of the imaging area.
This paper studies the possibility of using the scattering of cosmic muons to identify threatening high-Z materials. Various scenarios of threat material detection are simulated with the Geant4 toolkit. poca （Point o...
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This paper studies the possibility of using the scattering of cosmic muons to identify threatening high-Z materials. Various scenarios of threat material detection are simulated with the Geant4 toolkit. poca （Point of Closest Approach） algorithm reconstructing muon track gives 3D radiography images of the target material. Z-discrimination capability, effects of the placement of high-Z materials, shielding materials inside the cargo, and spatial resolution of position sensitive detector for muon radiography are carefully studied. Our results show that a detector position resolution of 50 μm is good enough for shielded materials detection.
The Cosmic Ray Inspection and Passive Tomography (CRIPT) collaboration has completed the testing of small muon detector prototypes and has commenced construction of a 12 layer, 4m(2) prototype muon scattering tomograp...
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ISBN:
(纸本)9781467301206
The Cosmic Ray Inspection and Passive Tomography (CRIPT) collaboration has completed the testing of small muon detector prototypes and has commenced construction of a 12 layer, 4m(2) prototype muon scattering tomography system. Three areas of CRIPT's progress are reported: (1) results from the testing of one of drift chamber muon detector prototypes;(2) algorithms for muon momentum estimation and tomographic image reconstruction;and (3) the status of the large prototype construction. The intrinsic resolution of the 2.4 m long, 1.2 m wide drift chamber muon detector prototype has been measured to be 1.73 mm perpendicular to the anode wire, and 2.9 mm parallel to the anode. A Bayesian estimator algorithm has been developed for muon momentum estimation. From simulations, the momentum resolution is expected to be highly asymmetric, varying from -18% to +92% integrated across the cosmic ray muon spectrum. A novel Point-of-Closest-Approach (poca) algorithm has also been developed for tomographic imaging. Multiple possible muon trajectories are assumed for each muon. The expected completion date for the construction is summer 2012, with first tomographic data following soon afterward.
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