Analyses of JAEA/FNS iron in-situ experiment with latest nuclear data libraries

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