POPULATION OF THE YRAST SUPERDEFORMED BAND IN PB-194

The yrast superdeformed (SD) band in Pb-194 has been populated by means of four fusion-evaporation reactions (W-184 + O-16, W-184 + O-17, Dy-164 + S-34, Dy-162 + S-36) leading to different angular momenta and excitation energies in the various compound nuclei. The yields measured for the so band relative to the total yield of the Pb-194 channel do not show any dependence on excitation energies and show only a very weak increase with angular momentum. The feeding pattern of the so band in Pb-194 is compared to similar data for so bands in neighbouring nuclei. All these results can be interpreted by the fission process (an important exit channel for all fusion reactions leading to Pb isotopes) which imposes a very low limit in the angular momentum of the Pb residual nuclei.