Quadrupole moment of superdeformed bands in ¹⁵¹Tb

The quadrupole moments of the first two superdeformed (SD) bands in the nucleus 151Tb have been measured with the Doppler Shift Attenuation Method (DSAM) using the EUROGAM γ-ray spectrometer. The first excited band (B2) is identical to the yrast SD band of 152Dy in terms of dynamical moments of inertia and γ-ray energies. The measured relative quadrupole moments of the yrast band (B1) with respect to the band B2 are nicely reproduced by self-consitent Hartree-Fock calculations. The variation of the Q0 value at the bottom of the yrast band suggests a large admixture between wave functions in the normal and the SD wells. This could explain the rather high deexcitation spin for the yrast band.