Measurement Of Fission Product Yield For ²³⁵U Induced By D-D Neutron

Nuclear data is the bridge linking nuclear physics experiments and practical applications.Among them,the yield of fission products,especially the yield of neutron-induced fission products,is widely used in many aspects such as experiments of fundamental nuclear,research of nuclear structure model,design of nuclear engineering,measurement of reactor component burnup,detection and verification of nuclear fuel.At present,there are high quality measurements data of ²³⁵U fission product yields induced by 14 MeV neutrons and thermal neutrons;however,there are few measured data on ²³⁵U fission yields induced by neutrons in 2³ MeV energy region.Furthermore,the measured data in this region has large divergence and uncertainty,which leads it's difficult to meet the practical application.This is because the greater uncertainty will bring unnecessary losses to users,reduce accuracy of industrial design,and cause various problems such as experimental errors.In addition,several single-energy neutrons energies-induce ²³⁵U nuclear reactions date,the lack of data,the ²³⁵U fission yield induced by several single-energy neutron,limits the research progress of this field.Therefore,it is necessary to conduct a precisely measurement of ²³⁵U fission yield induced by neutrons in this region.The neutron activation analysis and direct gamma spectrometry were used to experimentally measure and analyze the ²³⁵U fission yield induced by the?2.8±0.3?MeV neutron produced by D-D neutron source.The neutron irradiation experiment was completed on the CPNG-600 Cockcroft-Walton generator of the Chinese Institute of Atomic Energy,and the irradiation time of the uranium target was about 105 h.After the irradiation,the low background HPGe gamma spectrometers of China Institute of Atomic Energy and Lanzhou University were used to measure the gamma energy spectra of fission yield at different cooling times.Combining the theoretical calculation formula of yield and the characteristic?peak counts of the fission product,the cumulative yield of 22 kinds of fission products and relative yield data relative to ⁹⁹Mo are calculated.The sources of error are fully considered and the results are corrected.In addition,the errors and their sources,in neutron activation and direct gamma spectrometry in the measurement of fission yield,are also explored in detail.Finally,the chain yield of ²³⁵U fission induced by D-D neutrons source was given.The results were compared to ENDF/B-VII.1 evaluation data,and they have overall agreement,especially the position of light peak and heavy peak.The measurement results of this work improve the accuracy of ²³⁵U fission yield data induced neutron in the 2³ MeV energy region,and supplement the fission yield data of some important nuclides such as ⁹⁵Zr,⁹⁹Mo,¹⁴⁰Ba in this energy region.