Experimental and calculated spectra of neutron and photon leaking from iron ball mockups with Cf-252 source in center

One describes experiments and calculations to investigate into spectra of neutrons and photons emitted from 20, 40, 50, 60, 70 and 100 cm diameter ball mockups with a 252 Cf source in their centres. The calculations have been performed using the ROZ-6 code and the BNAB-78 28-group library of neutron constants. The experimental flows of > 0.8 MeV energy neutrons are, as a rule, higher than the calculated ones, the variations constitute 2-3 times. The derived data imply the need to define more precisely cross sections of elastic and inelastic scattering and radiation capture of neutrons at constant total cross sections of iron interaction with neutrons