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Angular distribution of alpha particles with respect to the spin direction of residual nuclei from fusion of 176-MeV ^^Ne with ^^^Nd has been measured with the spin spectrometer. Below the Coulomb barrier, the ratio of the 90° to 0° yields with respect to spin direction increases with decreasing E^. This effect is not shown by a statisticalmodel calculation using penetrabilities for spherical potentials, which suggests that the a-emitting nuclei are deformed with their longest axis perpendicular to the spin direction. If so, the deformation increases as the spin rises from ~ 34 to 64^. PACS numbers: 21.10.Ft, 23.60.+ e, 25.70.Fg, 27.70.+qThe shape and structure of the nucleus at high excitation and their evolution with spin are subjects of current interest. These properties of highly excited nuclei can be investigated by measurements of evaporated a particles/""^ We report here for the first time measurements of angular distributions of evaporated a. particles with respect to spin direction, using the unique properties of the spin spectrometer.'^"^ The spectrometer, a An y-ray multidetector system, determines the magnitude and the orientation of the spin of the residual nuclei on an event-by-event basis. This provides a sensitive method'^ to investigate changes in nuclear shape as a function of spin.A 176.6-MeV ^°Ne beam from the Oak Ridge isochronous cyclotron bombarded a 1.1-mg/cm^ Nd target enriched to 96.1% in mass 150. The a particles were measured in nine Si surface-barrier AE, J5 telescopes, of which two were at 80° and one was at 90° to the beam (-89° and 97° cm.). The A£^ detectors had a thickness of 75 jum and an acceptance cone of -6° half-angle. A Si detector at 8° identified evaporation residues

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The y-rays following the radioactive decay of 16~ into 16~ have been studied. The Lu source was produced in the 144Sm(19F, 3n) reaction at 85 MeV. Excitation functions, half-lives, 7-Y and y-X-ray coincidences and conversion electrons were measured. Two /3 + decaying states in 16~were found with half-lives of 36.2(3)s and 40(1)s. 16~ levels deduced from the decay of 16~ are presented.

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