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Information × Registration Number 0225U002547, (0124U000837) , R & D reports Title Highly efficient detectors of fast neutrons for demining systems based on the principle of neutron backscattering popup.stage_title Дослідження спектральних характеристик зворотньо розсіяних нейтронів детекторами на основі стильбену та LiI(Eu) Head Lytovchenko Serhii V., Доктор технічних наук Registration Date 18-03-2025 Organization V.N. Karazin Kharkiv National University popup.description1 The aim of the work is to solve the problem of increasing the efficiency of registration and sensitivity of fast neutron detectors based on oxide scintillators, due to the use of a combination of several mechanisms of neutron energy conversion in the substance of the oxide scintillator (i.e., the combined action of inelastic neutron scattering and their resonance capture). The main tasks to be solved are the following: - development and production of a gamma-neutron discriminator; - development and production of an electronic neutron flow intensity recorder; - modeling of scattered neutron fields from irradiated objects using the Monte method Carlo in order to optimize the "detector-sample-neutron source" system in relation to reduction of the influence of background gamma quanta during the detection of the studied samples; - estimation according to the statistical model of the energy of scattered neutrons producing cascade gamma quanta; - measurements of the intensities of backscattered neutrons in high-energy and resonant regions from the samples under study in order to optimize the choice of the type of scintillators; - evaluation of scintillator parameters from the point of view of optimal efficiency and sensitivity to backscattered fast neutrons from the studied samples. popup.description2  The aim of the work is to increase the efficiency and sensitivity of mine clearance systems with plastic casings. The use of techniques that include the fast neutron backscattering method makes it possible to increase the reliability of detecting small-mass mines. ZWO (ZnWO4) scintillation detectors, due to the increased efficiency of resonant and thermal neutron detection, can significantly increase the sensitivity of explosives detection. In addition, an oxide scintillator with a large atomic number effectively records high-energy gamma quanta that additionally arise in the mine due to the resonant properties of nitrogen N and oxygen O nuclei. The main attention is paid to the characteristics of nuclei and nuclear reactions with neutrons in the energy range from 0.025 eV to 14 MeV, which are part of explosives and detectors - H, C, N, O, Zn, W. The analysis was carried out using databases on reaction cross sections, energy of prompt and time-delayed gamma quanta from radiation and resonance capture reactions, and inelastic scattering. Particular attention was paid to the processes of interaction of resonant neutrons with nuclei and the resonant properties of mine nuclei. This is important when using detectors with a high resonant neutron capture energy limit, for example, ZnWO4, which has Eres (Zn) ~ 1-2 MeV The intensity of the flux of backscattered neutrons from urea-based mine mock-ups was experimentally investigated using stilbene-based detectors, which are sensitive to fast and resonant neutrons, and LiI(Eu) detectors, which are sensitive to thermal neutrons. A neutron discriminator based on a digital oscilloscope was developed to measure neutron fluxes. A script program was developed to analyze pulses from gamma-rays and neutrons by the trailing edge duration. A low-noise, high-speed signal preamplifier with a photomultiplier tube (PMT) was also developed. Product Description popup.authors Hirka Ihor O. Naumenko Liubov M. Onyshchenko Hennadii M. Sidletskyi Oleh Ts. Tarasenko Oleh А. Shchus Oleksandr Р. Yakymenko Ivan I. popup.nrat_date 2025-03-18 Close