Level structures in147Pmfrom147Nddecay

Abstract

The {gamma} and conversion electron spectra following the {beta} decay of {sup 147}Nd are measured using the HPGe detector and the miniorange electron spectrometer. The {sup 147}Pm level scheme comprising of 11 levels up to 686 keV excitation, interconnected by 29 transitions, is presented. The 649 keV (11) /(2) {sup {minus}} level, with six interconnecting (including two E3) transitions, is observed for the first time in decay studies. K-shell conversion coefficients for four transitions and L-shell conversion coefficients for five transitions are being reported for the first time. The I{sup {pi}}= (7) /(2) {sup +} spin-parity assignment for the 680 keV level is confirmed. Specific structure features of the {sup 147}Pm level scheme, depicting the unique coexistence of spherical shell model configurations, particle-phonon coupled multiplets, evolution of octupole collectivity, and well-developed rotational bands, are discussed; certain open questions about the spectroscopy and interpretation of the 633 and the 641 keV levels are highlighted. {copyright} {ital 1997} {ital The American Physical Society}