High-spin structure and multiphonon γ vibrations in very neutron-rich 114Ru

摘要

High-spin levels of the neutron-rich 114Ru have been investigated by measuring the prompt γ rays in thenspontaneous fission of 252Cf. The ground-state band and one-phonon γ -vibrational band have been extendednup to 14+ and 9+, respectively. Two levels are proposed as the members of a two-phonon γ -vibrational band.nA back bending (band crossing) has been observed in the ground-state band at ¯hω ≈ 0.40 MeV. Using thentriaxial deformation parameters, the cranked shell model calculations indicate that this back bending in 114Runshould originate from the alignment of a pair of h11/2 neutrons. Triaxial projected shell model calculations fornthe γ -vibrational band structures of 114Ru are in good agreement with the experimental data. However, whennusing the oblate deformation parameters, both of the above-calculated results are not in agreement with thenexperimental data.