The different samples of iron shields with empty slits were irradiated by 14 MeV neutrons. The samples with solid structures, central symmetrical, asymmetrical, and two slits were investigated in the experiments. The results of the measurements for the samples with a shield thickness of 500 mm which were obtained in the execution of the first year of the ISTC project No. 180 are represented in this report. The spatial distributions of the threshold reaction rates: In-115(n,n'), Zn-64(n,p), Fe-56(n,p) and F-19(n,2n) were measured. This set was added by the U-233(n,f) reaction. The experimental coefficients for mutual influence of two empty slits were derived. The method of gamma-heating rate measurements in iron by thermoluminescent detectors (TLD) was modified. Also, the effective threshold reaction rate parameters used in the experiments were calculated. (C) 1998 Published by Elsevier Science S.A. All rights reserved.
