Yuanzineng kexue jishu (May 2022)
Nuclear Data Evaluation and Chinese Evaluated Nuclear Data Library
Abstract
Nuclear data are the essential data for nuclear physics scientific research, the development of nuclear energy as well as the applications of nuclear technology, and it is an important bridge connecting fundamental nuclear physics research with nuclear engineering and nuclear technology application. Nuclear data play important roles in national defense, nuclear security, national economic development and basic science research etc. A nuclear data research system which including nuclear data measurement, nuclear data evaluation, model calculation, nuclear data library development and nuclear data integral benchmarking, has been established in China since 1960’s. A lot of highreliability nuclear data, highlevel methodologies and libraries have been achieved with the effect of the national nuclear research network since China Nuclear Data Center established in 1975. All the output feed the needs of nuclear energy and nuclear technology applications, and nuclear data research also prompted the development of nuclear physics study in China. The nuclear data evaluation is an important part of nuclear data research, and it involves experimental data evaluation, nuclear model calculation, recommendation, complicated physics checking of complete set of data, evaluated data file integral verification and validation, etc. This paper briefly introduces the main research procedure of nuclear data evaluation, corresponding theoretical models and calculation codes, and the method of the establishment and validation testing for the latest version of Chinese Evaluated Nuclear Data Library (CENDL32). Some notable advances in CENDL32 are noted, such as new evaluation of the nn and np scattering cross section, model dependent covariance data for main reaction cross sections of some fission product nuclides and the updated evaluation of nuclear reaction data of several key nuclides, such as 7Li, 233,235U, 56Fe, 240Pu, etc. The evaluated nuclear data integral verification and validation is the essential links in the application of nuclear data to nuclear engineering. In order to verify the physical rationality, systematic comparisons between CENDL-3.2 and other major evaluated libraries (e.g. ENDF, JENDL, BROND, JEFF and TENDL) have been implemented using a suite of criticality benchmarks from the International Criticality Safety Benchmark Evaluation Project, and compared with available experimental data. This paper also briefly introduces relevant benchmarking testing and application results based on the CENDL32, and the χ2 value obtained implies that CENDL32 has a potential remarkable improvement of predictions for 235U and Pu systems. The CENDL32 library also has good performances on the reactor physics simulation of PWR, VENUS3 shielding benchmark by ARES transport code, HTR10 benchmark, etc. In general, integral validation performance of the CENDL32 library is improved relative to the previous CENDL31 library.
