A novel decay channel of the 1⁺scissors mode: coupling to the vibrationalβ-excitation

Abstract

Abstract. The transitional nucleus 154 Gd was investigated using a combination of a photon scattering experiment and a γγ-coincidence study following the β decay of 154 Tb. A novel decay channel from the scissors mode to the band head of the β-band was observed. Its transition strength B(M1; 1 + sc → 0 + β ) was determined. An IBM-2 calculation reveals a correlation of this decay channel and the shape phase transition between spherical and deformed nuclei.