Decay scheme data for 239U, 154Eu and 140Ba/140La

Measurements of the major β- branching intensities in the decay of 239U to 239Np have been made by comparing γ-spectra obtained from 239U β- and 243Am α decay which both populate levels in 239Np. This comparison method eliminates the need for accurate internal conversion data, and the β- branching intensities are much more precise than those currently quoted in the literature. The half-life of the fission product 154Eu is being determined by monitoring the emission rate of the 1.27 MeV γ-ray relative to the emission rates of the 1.17 MeV and 1.33 MeV γ-rays of 60Co in two mixed 154Eu/60Co sources using a Ge(Li) detector. The best estimate of the 154Eu half-life is now 9.19 +- 0.24 y. Absolute emission probabilities of 21 γ-rays in the fission product pair 140Ba and 140La have been determined using 4πβ-γ coincidence techniques and Ge(Li) γ-ray spectroscopy. (Auth.)