Observation of Rotational Bands in Neutron-Rich 106Mo Nucleus

The rotational bands up to a spin of 16h in the neutron-rich 106Mo nucleus have been investigated by measuring high-fold prompt γ-ray coincidence events following spontaneous fission of 252 Cf with a Gammasphere detector array. The ground-state band, the one-phonon and two-phonon γ-vibrational bands, as well as a quasi-particle band have been confirmed and expanded. The other four collective rotational bands, three proposed as twoquasi-particle bands and one proposed as a β-vibrational band, have been newly observed. The characteristics of these collective bands and the possible configurations for the quasi-particle bands are discussed.