EVALUATION OF NEUTRON-INDUCED CROSS SECTIONS OF CHROMIUM, IRON AND NICKEL FOR JENDL-3NAIG Nuclear Research Laboratory 4-1 Ukishima-cho, Kawasaki-ku, Kawasaki 210, Japan Tetsuo Asami and Keiichi Shibata Japan Atomic Energy Research Institute Tokai-mura, Naka-gun, Ibaraki-ken 319-11, Japan Hisao Yamakoshi Ship Research Institute Shinkawa, Mitaka-shi, Tokyo 181, Japan Neutron cross sections of elemental Cr, Fe and Ni and their isotopes were evaluated for neutron energy between 0.01 meV and 20 MeV. New experimental data for resonance parameters and total and threshold reaction cross sections up to 1986 were utilized as much as possible. Theoretical calculations were performed with the combination of the preequilibrium theory, the statistical theory and the DWBA method. Level density parameters and preequilibrium strength were adjusted to fit the particle spectrum data and the excitation cross sections of threshold reactions. The results were compared favorably with recent experimental data of the double differential neutron emission spectra, the gamma-ray spectra and the gas production cross sections. The evaluation is being finalized reflecting the integral test results and a close comparison with differential data. KEYWORDS: neutron cross sections, Cr, Fe, Ni, element, isotopes, evaluation, JENDL-3 |