| A.Gorgen, R.M.Clark, M.Cromaz, P.Fallon, G.B.Hagemann, H.Hubel, I.Y.Lee, A.O.Macchiavelli, G.Sletten, D.Ward, R.Bengtsson |
Lifetimes of states in the triaxial strongly deformed bands of $^{163}$Lu have been measured with the Gammasphere spectrometer using the Doppler-shift attenuation method. The bands have been interpreted as wobbling-phonon excitations from the characteristic electromagnetic properties of the transitions connecting the bands. Quadrupole moments are extracted for the
zero-phonon yrast band and, for the first time,
for the one-phonon wobbling band. The very similar results found for the two bands suggest a similar intrinsic structure and support the wobbling interpretation. While the in-band quadrupole moments for the bands show a decreasing trend towards higher spin, the
ratio of the interband to the in-band transition strengths remains constant. Both features can be understood by a small increase in triaxiality towards higher spin. Such a change in triaxiality is also found in cranking calculations, to which the experimental results are compared. |
