Tsuneo Nakagawa, Yasuyuki Kikuchi and Sin-iti Igarasi

Japan Atomic Energy Research Institute
Tokai-mura, Naka-gun, Ibaraki-ken, Japan

Evaluation of nuclear data for transplutonium nuclides has been performed in the energy range from 0.01 meV to 20 MeV. The quantities evaluated are cross sections of total, elastic and inelastic scattering, fission, (n,2n), (n,3n) and (n,4n) reactions. The angular distributions and energy distributions of emitted neutrons and the number of neutrons per fission were also given for each nuclide. In a low energy range, resolved and unresolved resonance parameters were given to reproduce the cross sections. In a high energy region, theoretical calculations with optical, statistical and evaporation models were used except for the fission cross section which was determined from the experimental data or systematic trend. So far, evaluated data have been given for 20 nuclides; Am-241, 242, 242m, 243, 244, 244m, Cm-242, 243, 244, 245, 246, 247, 248, 249, Bk-249, 250 and Cf-249, 250, 251, 252. The evaluated results were compiled in the ENDF-5 format and will be stored in JENDL-3.

KEYWORDS: Evaluation, Nuclear Data, Americium, Curium, Berkelium, Californium, Resonances, Cross sections, Angular Distributions, Energy Distributions