FEEDING OF THE SUPERDEFORMED YRAST-BAND IN GD-149

The feeding pattern of the superdeformed yrast band in 149Gd has been found to remain essentially the same, using the 124Sn+30Si reaction at beam energies of 150, 155 and 160 MeV leading to different input angular momenta and excitation energies in the compound nuclear system. This similarity as well as the relative yields of the superdeformed states as a function of beam energy may be understood in terms of the nuclear level density dependence on deformation and the onset of fission. In addition, it has been shown that, at all three beam energies, the selection of high-energy gamma rays does not enhance the yield of the superdeformed yrast states. © 1990.