Speaker
Marco Cortesi
(Weizmann Institute of Science)
Description
A novel high-efficiency, one-dimensional fast neutron imaging detector intended for future fan-beam transmission tomography applications, was recently proposed. It consists of a multi-layer neutron-to-proton converter made of hydrogenous materials (polymer) coupled to a position-sensitive THGEM detector; the latter collects and multiplies the proton-induced electrons released in the gas gap between the converter foils, thereby sensing the impinging-neutron’s position.
We will briefly review the design, operational principles and expected performances of the new detector concept. We will report on the characterization studies and results of electron transport along the small gas gaps of the converter, which affects the performance of the detector, both in terms of detection efficiency and localization properties – measured with a multi-foil converter and aa 10x10 cm2 THGEM imaging detector; the experimental results are compared to Monte-Carlo simulations ones.
For irradiation with 2.5 MeV neutrons and a total of 300 converter foils, detection efficiencies of ~ 7% and a spatial resolution of round 1 mm are expected.
Among foreseen applications are neutron tomography in non-destructive testing for the nuclear energy industry, including examination of spent nuclear fuel bundles, detection of explosives & drugs, as well as investigations of thermal-hydraulics phenomena.
