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High-spin states in the transitional nucleus 158 Yb were populated via several (HI,4«) reactions. Two yrast bands were established up to I* = (40 + ) and (31""). In contrast to the negative-parity band up to 7 = 31 and the positive-parity states up to I = 24 which show collective rotational patterns, states with 7 ,r = 26 + -36 + exhibit a nearly vibrational excitation mode. Such a quasivibrational pattern suggests a gradual transition toward oblate shapes and is the first evidence for a "band termination" in a heavy nucleus.PACS numbers: 23.20.Lv, 21.10.Hw, 21.10.Re, 27.70.+q Rare-earth nuclei with neutron numbers 82

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The angular momentum dependence of large fragment production in long lived reactions is studied by measurements of fragment cross sections from reactions with substantially different angular momentum distributions and the coincident y-ray multiplicity distributions.The results indicate that the primary l-wave distributions move to larger mean values and decrease in width and skewness with increasing mass symmetry in the decay channel. The results also confirm that the partition of angular momentum in kinetic energy relaxed heavy-ion reactions is that expected for a rigidly rotating intermediate.