Prompt Gamma-Ray Spectroscopy Of The Mo-104 And Mo-108 Fission Fragments

The level structures of the neutron-rich Mo-104 and Mo-108 nuclei have been investigated by observing prompt gamma rays emitted in the spontaneous fission of Cm-248 With the EUROGAM spectrometer. Levels with spins up to 12HBAR have been observed and gamma branching obtained. The data can be satisfactorily described when Mo-104,Mo-108 are considered as axially symmetric nuclei: in Mo-104, rotational bands based on the ground state, the one-phonon and the two-phonon gamma-vibrational states and a quasiparticle state have been observed, whereas in Mo-108 the information is limited to the yrast band and the one phonon gamma band.