| A.Gorgen, G.B.Hagemann, I.Hamamoto, R.Bengtsson, R.M.Clark, M.Cromaz, P.Fallon, H.Hubel, I.Y.Lee, A.O.Macchiavelli, G.Sletten, D.Ward |
Wobbling is an excitation mode unique to triaxial nuclei. Even though it is a general consequence of triaxiality in nuclei, it has so far only been observed in the odd-mass Lu isotopes around $^{163}$Lu. The principal evidence for the wobbling mode is based on the pattern of rotational bands characterized and described by a wobbling phonon number and the decay between different bands belonging to the same family. A new measurement revealed lifetimes of states in an excited wobbling band for the first time and gave access to absolute transition probabilities for both in-band and interband transitions. A general
recipe how to derive quadrupole moments for triaxial nuclei from experimental data is discussed. The results show a remarkable
similarity of the quadrupole moments for the different bands, further supporting the wobbling scenario. A decrease of the quadrupole moments
is observed with increasing spin. This is attributed to an increase in triaxiality with spin, which can at the same time explain the
dependence of the interband transitions on spin. Such an increase in triaxiality is qualitatively reproduced by cranking calculations to which the experimental results are compared. |
