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The level structure of the N = 79 137Ce nucleus has been studied with the 137Ba(3He, 3n) reaction using in beam γ-ray and conversion electron spectroscopy. The level ordering in the vh11/2-1 × 2+ multiplet has been discussed on the basis of the triaxial rotor-plus-particle model which suggests a slightly oblate triaxial shape for 137Ce and the prolate-oblate shape transition in the Ce isotopes to occur between N = 77 and 79.

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Levels of the N = 83 nucleus 147Gd havre been investigated by in-besmy-rayTand conversionelectron spectroscopy using the 14 Sm(3He,3n) and 144Sm(~,n) reactions. We have observed 16 new lowand medium-spin levels in 147Gd. In addition to the previously kno~n 13/2 level we bare located tl 2 _ ~ t ~ * the / , 9/2 , 7/2 , 3/2 and (I/2) members of the ~f712x3 septuplet.Few years ago it was observed [1,2] the first excited state in the Z = 64, N = 82 nucleus 146Gd is 3-and this nucleus exhibits several features characteristic of a doubly closed shell nucleus. In the 146Gd region octupole excitations are of particular interest, partly due to the relatively low octupole phonon energy (I MeV lower than in 208pb) and partly due to the microscopic composition [3] of ~he octupole phonon.In 147Gd, the 997 keV 13/2 first excited state is predominantly a vfv/2x3 octupole excitation [4,5], and a twophonofi octupole state was observed for the first time in this nucleus [5].