LIFETIME MEASUREMENTS OF SCISSORS MODE EXCITATIONS IN DY-162,DY-164

The inelastic neutron scattering reaction has been used to populate kn own 1(+) scissors mode states in the deformed rare-earth nuclei Dy-162 and Dy-164. The electromagnetic decay properties of these states have been examined and the Doppler-shift attenuation method has been used to measure directly the lifetimes of these states. The M1 strengths de termined are in general agreement with those measured previously in nu clear resonance fluorescence experiments and support the conclusion th at these are collective structures; however, a significant discrepancy is found for three states near 3.1 MeV in Dy-164. Candidates for 2(+) rotational band members have been identified, and a previously sugges ted gamma-ray branch from a spin-1 state to the gamma vibration in Dy- 164 has been observed.