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Information × Registration Number 0226U002860, (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 ефективності та чутливості детекторів на основі оксидних сцинтиляторів ZWO, CWO, GSO до розсіяних нейтронів Head Lytovchenko Serhii V., Доктор технічних наук Registration Date 09-03-2026 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 At the stage of studying the efficiency and sensitivity to backscattered neutrons from a Pu-Be source with ZWO, CWO, and GSO scintillators for mine clearance systems with plastic casings, the ZWO scintillator was found to be highly sensitive to the backscattering of fast neutrons. The ZWO (ZnWO4) scintillation detector, due to its high efficiency in registering resonant neutrons by Zn nuclei, makes it possible to significantly increase the sensitivity of mine detection by registering secondary gamma quanta that arise in the scintillator when a neutron is captured. ZWO also effectively registers external gamma rays arising in the mine material when interacting with neutrons, due to the resonant properties of nitrogen N and oxygen O atomic nuclei. To increase the sensitivity of the technique, which requires registering low-energy photons arising from the excitation of final nuclei in the inelastic scattering reaction, as well as from compound nuclei in the resonant capture reaction, a single-electron mode of the PID was used. A broadband (300 MHz band) low-noise preamplifier with a gain of 3000 and an input bias current of 2 pA was used for the input stage. An important result obtained in ZWO measurements is a significant increase in the counting efficiency of the method to ~ 5*10^3 pulses/(neutron) (exposure 200 s, statistical error 2%) compared to a stilbene scintillator of the same volume, which was studied in a conventional counting mode using a gamma-neutron discriminator and had an efficiency of ~ 0.9 pulses/(neutron) (exposure 80 minutes, statistical error 3%). Thus, experimental studies of the efficiency and sensitivity to scattered neutrons of ZWO-based detectors using single-electron mode indicate the possibility of a significant increase in the sensitivity of the demining system to gamma-neutron radiation when using a ZWO scintillator. Product Description popup.authors Shchus Oleksandr Р. Tarasenko Oleh A. Sidletskyi Oleh Ts. Marchenko Oksana Igor Girka Hennadii M. Onyshchenko Ivan I. Yakymenko Pavlo S. Kyzym popup.nrat_date 2026-03-09 Close