Excited states of 135La populated by the decay of 135Ce

The decay of 135 Ce was studied with a \(\pi\sqrt{2}\) iron-free β-spectrometer, a Ge(Li) detector and an e - –γ delayed coincidence technique. From internal conversion and γ-ray studies 21 new transitions were observed. The multipolarities with mixing ratios of 10 transitions were determined from the L-subshell conversion ratios. From these results a revised decay scheme is proposed as follows: 0[5/2 + ], 119.47[7/2 + ], 206.37[5/2 + ], 265.42[3/2 + ], 299.92[1/2 + ], 665.30[5/2 + ], 783.38[3/2 + ], 828.20[3/2 + ], 872.15[1/2 + (3/2 + )], 984.29[1/2 + , 3/2 + ], 1171.16[3/2 + (1/2 + )], 1438.95[1/2 + , 3/2 + ] and 1767.3[1/2, 3/2], where level energies are written in keV. Large E2 enhancements are found for the 34.5, the 86.9, the 265.4 and the 299.9 keV transitions.