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We found ENDF/B-VIII.0 caused the following problems through our analyses of the iron insitu experiment at JAEA/FNS; 1) the neutron flux of 1 - 10 keV is overestimated more in the shallower region of the iron assembly, 2) the reaction rate of 115In (n,n’)115mIn is underestimated more in the deeper region, 3) the neutron flux above 10 MeV is underestimated more in the deeper region. The reasons for these problems were investigated in detail and it was specified that the inelastic scattering data of 56Fe in ENDF/BVIII. 0 mainly caused the first and second problems and that the cross section of the (n,2n) reaction and the angular distribution data of the elastic scattering of 56Fe in ENDF/B-VIII.0 caused the third problem.

As a benchmark test of JENDL-4.0/HE released in 2015, we have analyzed the concrete and iron shielding experiments with the quasi mono-energetic 40 and 65 MeV neutron sources at TIARA in JAEA by using MCNP5 and ACE files processed from JENDL-4.0/HE with NJOY2012. As a result, it was found out that the calculation results with JENDL-4.0/HE agreed with the measured ones in the concrete experiment well, while they underestimated the measured ones in the iron experiment with 65 MeV neutrons more for the thicker assemblies. We examined the 56 Fe data of JENDL-4.0/HE in detail and it was considered that the larger non-elastic scattering cross sections of 56 Fe caused the underestimation in the calculation with JENDL-4.0/HE for the iron experiment with 65 MeV neutrons.

We have studied reasons of differences of KERMA factors and DPA cross-section data among nuclear data libraries. Here the KERMA factors and DPA cross-section data included in the official ACE files of JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 are examined in more detail. As a result, it is newly found out that the KERMA factors and DPA cross-section data of a lot of nuclei are different among JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 and reasons of the differences are the followings: 1) large secondary particle production yield, 2) no secondary gamma data, 3) secondary gamma data in files12–15 mt = 3, 4) mt = 103–107 data without mt = 600 s–800 s data in file6. The issue 1) is considered to be due to nuclear data, while the issues 2)-4) seem to be due to NJOY. The ACE files of JENDL-4.0, ENDF/B-VII.1 and JEFF-3.2 with these problems should be revised after correcting wrong nuclear data and NJOY problems.