Multipole mixing ratios of γ-transltions in 182W

Abstract

γ-γ directional correlation experiments were performed on 14 cascades in 182W populated from the β − decay of 182Ta(115 d). Two Ge(Li) detectors were used in a coincidence arrangement, and the 182Ta sources were dissolved in HF acid to minimize extranuclear perturbations. For the 1189keV, 2 − → 2 + transition, the measured directional correlation coefficients are consistent only with multipole mixing ratios δ ( M2 E1) = 0.45 ± 0.03 and δ (E3 E1) = −0.67 ± 0.07 . These mixing ratios are discussed and compared with the known conversion coefficients for the 1189keV transition. The E2/M1 multipole mixing ratios determined are (energy in keV): δ(66) = 0.15 ± 0.15, δ(85) = 0.31 ± 0.05, δ(114) = 0.31 ± 0.05, 0.56 ≦ δ(179) ≦ 1.36, δ(1121) = 12 +2 −1, and δ(1231) = −(32 +142 −15). The measured M2/E1 mixing ratios are: δ(68) = 0.03 ± 0.02, δ(152) = 0.014 ± 0.013 and δ(156) = −0.13 ± 0.19.