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Levels in the149Pm nucleus populated via149Nd decay were studied using the low temperature nuclear orientation technique. The parent149Nd nuclei were oriented in a gadolinium host. The normalized gamma-ray intensities were determined for twenty five transitions in the daughter149Pm nucleus. The spins of the149Pm levels at 288.2 and 425.3 keV were determined as 9/2 and 7/2, respectively, and for several other149Pm levels the previous spin-assignments could be unambiguously confirmed. Substantial new information on multipole mixing ratios of gamma-transitions in149Pm is presented. Low-energy level spacing in the149Pm nucleus is found to be in reasonable agreement with recent particle-rotor model calculations including the variable moment of inertia.

Abstract: The decay of238Np oriented at low temperatures in gadolinium host was investigated. Multipole mixing ratios for beta-transition to the level 1028.6 keV and nine gamma-transitions in238Pu were calculated from the anisotropies of gamma radiation. The attenuation factor for the isomeric state of238Pu at 1082.6 KeV and orientation parameters for238NpGd were deduced from the experimental results.

Abstract: Angular distribution of gamma radiation from the decay of205Bi oriented at low temperatures in gadolinium host was investigated. The orientation parameters B2 and B4 were determined. The spin 9/2 could be uniquely assigned to the positive-parity level at 2252.3 keV. No attenuation was observed for the isomeric level at 1013.8 keV. Seven new values of multipole mixing ratios of E2/M1 gammatransitions in205Pb were determined, two earlier measured values were confirmed.

Abstract: The angular distribution of γ-radiation from the decay of239Np oriented at low temperatures in gadolinium host was investigated. The orientation parameters B2 and B4 were determined. The attenuation factors for two long-living states in239Pu at 391.5 keV and 285.4 keV were calculated. From the anisotropies measured the multipole mixing ratios for 11 gamma-transitions in239Pu were deduced. The results obtained support the assignment of spins of the levels at 492.2 keV and 391.6 keV as 3/2− and 7/2−, respectively.