Transitional nuclei. I. Decay of 150Pm to levels of 150Sm

Abstract

The energies and relative intensities of the γ transitions following the 150Pm decay have been measured using high-resolution Ge(Li) detectors. A total of 140 γ rays was observed and 117 of these transitions could be traced to 34 levels in the 150Sm nucleus. A large amount of information on the structure of the 150Sm nucleus could be extracted by a direct comparison of measured spectra inside and outside a well-type Ge(Li) spectrometer. In such a way sum lines arising from two (or more) coincident y rays could be detected easily, thus giving the possibility of obtaining direct coincidence information on the 150Pm decay in spite of its short half-life (2.7 h) and high complexity. Spin and parity assignments for levels in 150Sm are tentatively given, by also taking advantage of previous experimental studies available on this nucleus.