Critical verification for TRX and BAPL benchmarks based on ENDF/B-VIII.0 using DRAGON code

Abstract The aim of this paper is to present the critical verification for TRX and BAPL benchmarks between the ENDF/B-VIII.0 and ENDF/B-VII.0 library. Using DRAGON5.0.6 code with 281-group WIMS-D and DRAG library, the integral parameters for TRX and BAPL benchmarks are compared to the Monte-Carlo code and experimental values. For the verification of DRAGON code, the influence of tracking method, resonance self-shielding method, and leakage model are investigated in this paper. The results indicated that the combination methods of collision probability method, equivalence theory, and P1 leakage model have better accuracy in TRX and BAPL benchmarks. For the comparison of ENDF/B-VII.0 and ENDF/B-VIII.0 library, the difference of integral parameters is small between the ENDF/B-VII.0 and ENDF/B-VIII.0 library. The relative error of ρ28 and δ25 is less than 1%. However, the accuracy of δ25 and C* is underestimated by about 1.0%∼1.5% in ENDF/B-VIII.0 library. It means that the fission cross section for U-235 is overestimated in ENDF/B-VIII.0 library and the 2-group cross section comparison is consistent with this tendency. Therefore, the absorption cross section for whole region is increased in thermal energy group, which finally leads to the keff and kinf decreased in ENDF/B-VIII.0 library. Compared with the experimental values in TRX and BAPL cases, the integral parameters in ENDF/B-VIII.0 are more accurate than the ENDF/B-VII.0 library.