Nuclear orientation study of the decay ofLum177

Abstract
Angular distributions of 37 γ rays were observed following the decays of 161-day Lum177 and 6.8-day Lug177 polarized at low temperatures in the ferromagnetic cubic Laves-phase compound ZrFe2. The magnetic moment of the Lum177 was deduced to be |μ|=(2.74±.21)μN, in excellent agreement with the value μ=+2.59μN computed assuming the Lum177 to be the three-quasiparticle state 72+[404]p,92+[624]n,72[514]n. The magnetic hyperfine fields of Lu, Ta, Sc, and Co in ZrFe2 were deduced from the corresponding γ-ray anisotropies. Decays proceeding through the 1.1-sec Hfm177 were observed to show characteristic relaxation times of T16.7 sec. The E2M1 mixing ratios of numerous intraband transitions in Lu177 and Hf177 were deduced, and the corresponding (gKgR)Q0 values were computed. Several interband M2E1 mixing ratios were deduced and were compared with calculations based on the Nilsson model including first-order Coriolis mixing. The 0-180° asymmetries of several Lu177 transitions were observed in an effort to see if parity mixing effects might be present due to the particularly close-lying opposite parity states of