Of decay Eu 152 and Eu 152m

Abstract

Using magnetic and scintillation spectrometers and coincidence techniques the radiations from pile-irradiated natural Europium have been studied. The energies of a number of beta- and gamma-rays and internal conversion lines were measured and isotopic assignments were made from the coincidence data. The internal conversion coefficients of a number of the transitions are determined from measurements of the relative intensities of gamma-rays and internal conversion lines. Decay schemes are proposed for the two isomers of Eu 152 and plausible spin and parity assignments for some of the excited states of Sm 152 and Gd 152 are presented. The difference in level structure between these two nuclei is discussed in the light of the Bohr-Mottelson unified model and it is suggested that some of the high-lying excited states may possibly be interpreted as collective vibrations of the electric quadrupole and electric octupole type.