High-sensitivity fast neutron radiography system

Abstract

Introduced in this paper is a fast neutron radiography system, which is mainly composed of a scintillation fiber array and a scientific grade optical CCD. The 14 MeV neutrons produced by deuterium-tritium fusion reactions, penetrate through objects and fall into a 50 mm×50 mm scintillation fiber array, and the neutron radiation is converted to green light (496 nm). The array has a length of 100 mm, consisting of 100×100 square scintillation fibers each with a cross-section of 500 μm×500 μm. For 14 MeV neutrons, the detection efficiency is as high as 21.4%. To avoid direct radiation from neutrons, the CCD is coupled to the array by a mirror and lens optics. By taking into account the factors affecting image quality, the resolution is estimated to be 1.5 mm. Several neutron radiographs have been obtained successfully in experiments carried out on K400 neutron generator.