Recoil-distance Doppler-shift lifetime measurement of low-lying superdeformed states in 194Hg

The lifetimes of three low-lying states in the superdeformed (SD) yrast band of 194Hg were measured applying the recoil-distance Doppler-shift method. As the deduced transition quadrupole moments Qt are equal within the experimental uncertainties to those extracted from a Doppler-shift attenuation method (DSAM) measurement for the high-lying states of the band, the assumption that the decay out of SD bands does not strongly affect the structure of the corresponding states is corroborated. By a simple mixing model, the decay can be described assuming a very small admixture of normal-deformed (ND) states to the decaying SD states. The deduced ND mixing amplitudes for the yrast SD bands in 192,194Hg and 194Pb are presented along with average transition quadrupole moments for the lower parts of the excited SD bands in 194Hg.