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تسجيل مستخدم جديدConcept of a novel fast neutron imaging detector based on THGEM for fan-beam tomography applications
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The conceptual design and operational principle of a novel high-efficiency, fast neutron imaging detector based on THGEM, intended for future fan-beam transmission tomography applications, is described. We report on a feasibility study based on theoretical modeling and computer simulations of a possible detector configuration prototype. In particular we discuss results regarding the optimization of detector geometry, estimation of its general performance, and expected imaging quality: it has been estimated that detection efficiency of around 5-8% can be achieved for 2.5MeV neutrons; spatial resolution is around one millimeter with no substantial degradation due to scattering effects. The foreseen applications of the imaging system are neutron tomography in non-destructive testing for the nuclear energy industry, including examination of spent nuclear fuel bundles, detection of explosives or drugs, as well as investigation of thermal hydraulics phenomena (e.g., two-phase flow, heat transfer, phase change, coolant dynamics, and liquid metal flow).
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