E2 decay characteristics of the M1 scissors mode of Sm 152
The E2/M1 multipole mixing ratio of the 1sc+→21+γ-ray transition and therefore the F-vector E2 decay of the scissors mode of the shape-phase transitional nucleus Sm152 have been measured with the nuclear resonance fluorescence method at the High-Intensity γ-ray Source (HIγS). Furthermore, parity quantum numbers of several dipole-excited states have been remeasured, making use of the polarized γ-ray beam at HIγS, and partially reassigned. The new data enable an unambiguous determination of the proton and neutron effective boson quadrupole charges within the proton-neutron interacting boson model. With the well-constrained parameter set, a new mixed-symmetry state is predicted.