Yrast states up to spin 18 have been identified in ¹³²Ce. The energies and spins of the levels suggest the existence of two fairly well-behaved collective bands. The results are compared with those obtained in the rare-earth deformed region.
The isotopes ¹³⁰,¹³²,¹³⁴,¹³⁶ Ce are investigated by means of the reactions ¹¹⁸,¹²⁰,¹²²,¹²⁴ Sn(¹⁶O, 4n) at bombarding energies between 68 and 76 MeV. From lifetime measurements a reduction of the collective behaviour is observed with increasing neutron number. Yrast cascades of rotational structure are identified up to angular momenta I=16⁺ or I=18⁺ in ¹³⁰,¹³²,¹³⁴ Ce. These cascades show a strong “back-bending” effect. In ¹³⁶ Ce no such simple yrast cascade could be found.