Spins of the 2350, 2516, and 2547 keV levels in 140Ce determined from γ-γ directional and polarization-directional correlations

Directional correlations and polarization-directional correlation have been measured for different γ cascades in 140Ce, populated from the decay of 140La. Combination of Ge(Li) and INa(Tl) detectors were used in both experiments. For the polarization-directional correlation measurement a planar Ge(Li) detector was employed as the linear polarization analyzer. Combination of the results of these measurements gives unique spin assignments of 5-, 4+, and 1+ for the 2350, 2516, and 2547 keV levels, respectively. The determined mixing ratios are delta (131) = -0.33 +- 0.04, delta (267) = 0.39 +- 0.05, delta (432) = 0.54 +- 0.10, delta (868) = -0.034 +- 0.007, and delta (951) = 0.10 +- 0.03