George P. Ford

Half-life of 238Pu☆

Abstract The half-life of 238 Pu has been measured by determining its rate of growth from 242 Cm. The weighted average of two determinations is 86·41 years, with an estimated error of 0·3 year.

Half-life of Pu236☆

Abstract The half-life of the alpha emitter, Pu236, was measured by a direct decay method. Corrections were applied for the alpha-emitting daughters of Pu236. The results of three sets of data were: 2·855 yr, s = 0·009 yr; 2·817 y, s = 0·04 yr; 2·836 yr, s = 0·021 yr. The weighted average is 2·851 yr with s = 0·008 yr.

FORE-AFT YIELDS OF FRAGMENTS FROM 14-MEV NEUTRON-INDUCED FISSION

Abstract The yield of Zr97 and Ba139 fission fragments in the direction of 14-MeV neutrons inducing fission of Np237 and U235 was measured relative to the yield in the opposite direction. The fore-aft isotropy found from these measurements agrees with the compound nucleus theory of fission.

Independent isomer yield ratio of 90Rb

Abstract The independent isomer yield ratio for 90Rb from thermal neutron fission of 235U has been measured by use of a new technique involving a pulsed reactor and an on-line mass spectrometer facility. The observed isomer yield ratio of 8.7 ± 1.0 is one of the largest ratios measured for a low energy fission process. However, a statistical model analysis shows that the average angular momentum (J = 4.5) deduced from this isomer yield ratio is consistent with average angular momentum for other products from low energy fission.

Fermi-function integrals for finding relative beta-group intensities

Values are presented of the definite integral I(Z, Tmax), which is related to the relative number, N, of electrons in a β−-group with end point energy Tmax by the simple expression N = a2Tmax2I(Z, Tmax), where a is the y-intercept in the Fermi-Kurie plot, I ( Z , T max ) = ∫ 0 T max f ( Z , T ) h ( T ) d T , where f is the Fermi function and h ( T ) = ( T + 1 ) ( 1 − T / T max ) 2 [ T ( T + 2 ) ] − 1 / 2 T max − 2 . The Z-ranges is 10(1)109; the Tmax-range is 0.1(0.05)0.4, 0.5(0.1)5.2.