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The /T decays of Ta 182 and Ta 183 into excited states of W 182 and W 183 have been studied using a curved crystal gamma-ray diffraction spectrometer and a homogeneous field, ring focusing beta-ray spectrometer. In each case de-excitation of the daughter nucleus gives rise to complex gamma-ray and conversion electron spectra. Energies and relative intensities of gamma rays and conversion lines arising from 27 transitions in W 182 and 29 transitions in W 183 are presented. Internal conversion coefficients and multipolarities have been deduced for most of the transitions and together with the gamma-ray energies form the basis of decay schemes proposed for both W 182 and W 183 . The two decays are reported together be-cause of the close experimental relationship which existed between them as a consequence of the method used for their production, namely, simultaneous production of Ta 182 by single neutron capture and Ta 183 by double neutron capture from stable Ta 181 . A corollary result is the value 1.3 X10 4 barns for the thermal neutron cross section of Ta 182 .An interpretation of these results on W 182 in terms of collective rotational motion has been given by A. Bohr and collaborators [Kgl. Danske Videnscab. Selskab, Mat.-fys. Medd. 29,.No. 9 (1955)]. z 0.1 0.05 0.02

A study has been made of the gamma radiation following the decay of Ir 192 . The energies, intensities, internal conversion coefficients and multipolarities of the gamma transitions have been determined. Energy level schemes for the daughter nuclei, Pt 192 and Os 192 , are proposed. The spins and parities of most of the levels are given.The spin of the first excited state of Mn 55 at 128 kev has been measured in the electric excitation process with 3-Mev alpha particles. Determinations of the K conversion coefficient and the angular distribution of the gamma rays lead to a spin assignment of 7/2" for the excited state and multipolarity Ml for the transition to the ground state. The K conversion coefficient (ax=0.0144db0.003) wa s measured by comparison with the known coefficient of the 137-kev transition in Ta 181 . The spin, parity, and transition probability are consistent with those expected for a rotational state.