ИСПОЛЬЗОВАНИЕ ПРЯМЫХ ИНТЕГРАЛЬНЫХ ТЕСТОВ СО СТАНДАРТИЗИРОВАННЫМ СПЕКТРОМ ДЛЯ ТЕСТИРОВАНИЯ СЕЧЕНИЯ ЗАХВАТА ОСКОЛКОВ ДЕЛЕНИЯ

Abstract

The paper presents the results of validation for the capture cross section of the main fission product (FP) nuclides from different neutron data libraries on the results of measurements in integral experiments. A list of the main fission products for various types of fast reactors with various burnups of fuel is defined. When fissioning fuel nuclides in a nuclear reactor, numerous fission products are formed. The most important characteristic of fission products is the neutron capture cross section, as a result of which the valuable neutron for maintaining the fission chain reaction disappears. During long campaigns, the accumulated fission products can lead to a decrease in the criticality of the reactor to ~ 7 %. The evaluated neutron data for the main set of FP nuclides are contained in national libraries of evaluated neutron data. Evaluation of neutron data, as a rule, is carried out on the basis of experimental data from the international EXFOR database using various computational models of nuclear interactions. Often, the evaluated data is very different from each other. Evaluated data can be tested using integral experiments. To test the capture cross section for FP nuclides, direct integral experiments at the CFRMF reactor and experiments in which the neutron spectrum is close to the Maxwell spectrum with a spectrum temperature of kT = 30 keV were used. The first of the above experiments is a dosimetric benchmark experiment, given in the ENDF-202 benchmark experiment handbook. The second type of experiment underlies the recommendations for the MACS capture cross section for nuclides from the KADONiS astrophysical database.