New transitions and levels in 148 Ce have been observed in a γ-γ-γ coincidence study from the spontaneous fission of 252 Cf with Gammasphere detector array. The ground band has been extended up to I π = 22 + , and side bands are extended with I = 2 stretched transitions and I = 1 crossing transitions. The observed level scheme is interpreted in terms of possible octupole correlations. Two sets of interwined positive-and negativeparity bands with the simplex quantum numbers s = ±1 are suggested. The results of B(E1)/B(E2) branching ratios indicate that the octupole correlations in 148 Ce are strong.

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High-spin, even-parity bands in neutron-rich 108, 110, 112 Ru nuclei were reinvestigated and considerably expanded by measuring many-fold prompt γ-ray coincidence events following the spontaneous fission of 252 Cf with Gammasphere. Our high statistics data allow us to detect weaker transitions and bands not previously published. Also, gamma branching ratios, which are important for theory, are carefully measured from all levels. In 110 Ru , we find a doubling of levels for both ground and quasi-gamma bands above the 8+ levels. There are likely two-phonon quasi-gamma bands in 110, 112 Ru , as well as a bandhead level in 108 Ru . The odd–even spin energy band staggering observed in the quasi-gamma bands in 108, 110, 112 Ru and the doubling of levels in 110 Ru present a challenge to theory.

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