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Information × Registration Number 0216U003887, 0111U001940 , R & D reports Title Study of Nuclear Properties in Reactions with Filtered Neutrons and the Development of Nuclear Data Base for Fundamental and Applied Problems popup.stage_title Head Gritzay Olena Oleksandrivna, Кандидат фізико-математичних наук Registration Date 23-02-2016 Organization Scientific Center "Institute for Nuclear Research" of National Academy of Sciences of Ukraine popup.description2 The aim of investigation: study of nuclear and physical properties of atomic nuclei ar KRR, in particular at neutron filtered beams; modernization of existing and adoption of new experimental and computational methods; development of non-destructive analysis of stoichiometric ratio in metal hydrides with use of slow neutrons; update and completion of information and programm support for scientific and information supply of nucear data users as in institute, so as outside. Compilation of experimental data received by Ukrainian investigators into the International library of experimental nuclear data. Investigation methods and routines: neutron spectrometry using gas-filled proportional counters; determination of total neutron cross sections with using neutron transmission method for investigated samples; isolated resonance parameters evaluation methods; method of determination of hydrogen content in metal hydrides at the basis of observed experimental total neutron cross sections of investigated samples; developmet of codes and programs for update and completion of information and program supply. Interference neutron filter with average energy 5.6 keV was developed and calculated using Evaluated nuclear data libraries(ENDL) . Interference neutron filter on the base of Manganese with average energy 275 keV was developed and tested. New modifications of filters to select the neutrons with energies 120-160 кеV were developed. Installation for total neutron measurements using scattering neutrons was modified. Metod to obtain the set of averaged neutron cross sections using the measured sample transmissions and modified neutron beams with closely lying neutron lines was developed. The method was developed for determination of resonance parameters for isolated nuclear level using the resuls of total neutron cross sections measurements obtained at the same filter but with the small movement of average energy with the help of neutron scattering at nuclei-scatterers. Method for expermental testing of total neutron cross sections using the measurements at neutron filtered beams to remove the contradictions in ENDL was developed Average total neutron cross sections for natural Carbon in 9 enegy regions (91,94-172,50; 92,95-144,78; 141,89-163,61; 86,24-129,40; 122,16-142,06; 137,31-160,91; 75,30-136,22; 128,80-147,78; 145,02-161,91; 92,64-167,15 кеV) were measured using the set of transmissions and modified filters. To calculate the cross sections the new method for spectra processing was developed for closely lying neutron lines.The results of average total neutron cross section measurements for natural Carbon were analysed for average energies 2, 12, 24, 58, 133 and 144 кеV of neutron filtered beams. Averaged total neutron cross sections for 52 Cr at 4 energy regions 48,6-57,7; 45,8-55,3; 42,5-52,3; 38,1-48,6 кеV were defined using the method of moving the energy line of filter. Using the mentioned methods the neutron resonance parameters (E0, Гn та R) were evaluated for 52Cr total neutron cross section in the regionі 50 кеV from data obained at neutron filtered beams. At neutron filtered beam the new method for testing the total neutron cross section data in differend ENDLs was experimentally approved to remove the discrepances in cross sections in ENDLs. Method of nondestructive analysis of metal hydrides was developed using the slow neutrons. This method is founded on the results of experimentally measured total neutron cross sections using neutron transmission of hydride samples. At the example of TiHn it was shown that the ratio n - metal/hydrogen may be defined with accuracy near 1%. Monte Carlo method was used to calculate the neutron beams and spectra in horizontal channels of VVR-M reactor with using the low-enriched fuel. Algorithm and new version of code complex FILTER were developed for new filter calculations. The updating of information and program filling of UKRNDC site was prepared for student education and needs of different users in Ukraine. Product Description popup.authors Волковецький Степан Петрович Ворона Петро Миколайович Гримало Анна Костянтинівна Кальченко Олександр Іванович Лібман Володимир Абрамович popup.nrat_date 2020-04-02 Close