Third IAEA evaluation of the 2200 m/s and 20/sup 0/C Maxwellian neutron data for /sup 233/U, /sup 235/U, /sup 239/Pu, and /sup 241/Pu

A new consistent set of best values of 2200 m/s and 20/sup 0/C Maxwellian neutron cross-sections, fission-neutron yields, and Westcott g-factors are presented for U-233, U-235, Pu-239 and Pu-241, and of related reference values such as the spontaneous fission-neutron yield of Cf-252, the mean fission-neutron spectrum energies of the five nuclides named, the ..cap alpha..-decay half-lives of U-233, U-234 and Pu-239 and others. This consistent set of values is derived from a multi-parameter least-squares fit of all available experimental data, after reviewing and, where feasible, re-assessing the authors' quoted values and errors usually after consultation with the authors. The new best set of values is significantly different from that of the Second IAEA Review of 1969. The major changes are due to new lower experimental values of ..nu..-bar (Cf-252) and of half-lives. Also discussed are some disturbing unresolved discrepancies among experimental data, which leave the accuracies of some parameters, for example the uranium fission cross-sections, still unsatisfactory. 3 tables, 2 figures. (auth)