Concept of a novel fast neutron imaging detector based on THGEM for fan-beam tomography applications

摘要

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