Fitting and optimal grouping on gamma reliability data : Duan Wei and C. K. Shau. IEEE Trans. Reliab.R-36, 595 (1987)

Abstract

Exsting experimental thermal, fast, and 14-MeV neutron-induced fission-product cumulative and independent yieds have been compiled, corrected to common reference values, and listed in tabular form for the following fissile nuclides:Thermal-neutron fission: cumulative yields for 227Th, 229Th, 233U, 235U, 239Pu, 241Pu, 241Am, 242Am, 245Cm, 249Cf, 251Cf, 254Es, and 255Fm; independent yieds for 233U, 235U, 237Np, 238U, and 239Pu.Fast-neutron fission: cumulativ yields for 227Ac, 231Pa, 232Th, 233U, 235U, 237Np, 238U, and 239Pu; independent yields for 235U and 238U.14-MeV-neutron fission: cumulative yields for 231Pa, 232Th, 233U, 235U, 237Np, 238U, and 239Pu; independent yields for 232Th, 233U, 235U, 238U, and 239Pu.11-MeV-neutron fission: cumulative yields for 232Th.3-MeV-neutron fission: cumulative yields for 231Pa, 232Th, and 238U.1.1-MeV-neutron fission: cumulative yields for 237Np.From these experimental values the unknown independent yields are deduced empirically for thermal-neutron fission of 233U, 235U, 239Pu, and 241Pu; the fast fission of 232Th, 233U, 235U, 238U, 239Pu, 240Pu, and 241Pu (the chain yields for 240Pu and 241Pu used at this energy being predictions); and the 14-MeV-neutron fission of 232Th, 233U, 235U, and 238U.Finally, by the fitting of the preceding information to condition equations derived from the conservation laws, adjusted sets of chain and independent yields are calculated for thermal fission of 233U, 235U, 239Pu, and 241Pu; fast fission of 232Th, 233U, 235U, 238U, 239Pu, and 241Pu; and 14-MeV fission of 232Th, 233U, 235U, and 238U. The literature search is probably complete to the end of 1975; some 1976 results are included.This paper replaces and makes obsolete the following UKAEA reports: AERE-R7209, AERE-R7394, AERE-R7680, and AERE-R8152.