Reinvestigation of the α-decays of 249Cf and 233U

Abstract

The alpha-particle decay of 249Cf has been reinvestigated using coaxial and planar HPGe detectors. Energies and emission probabilities of thirty γ-rays were measured, of which nine are reported for the first time. All transitions have been included in the 245Cm level scheme suggested in this work: 14 excited states are found to be fed and assigned to 4 rotational bands. The I π = 11 2 − member of the 7 2 [743] Nilsson state was found to be fed at 772.3 keV. Alpha-particle transition probabilities were calculated from the revised 249Cf decay scheme. The alpha-particle decay of 233U has been reinvestigated using a UO 2 2+ source purified continuously from daughters by ion exchange chromatography. Energies and intensities of 178 γ-rays were determined, of which 49 are reported for the first time. γ-γ coincidence studies were also performed to help in the construction of the 229Th level scheme.