Abstrakt
Multi-step cascade gamma-ray spectra from the neutron capture at isolated resonances of Dy-161 nucleus were measured at the LANSCE/DANCE time-of-flight facility in Los Alamos National Laboratory. The objectives of this experiment were to confirm and possibly extend the spin assignment of s-wave neutron resonances and get new information on photon strength functions with emphasis on the role of the M1 scissors mode vibration.
The preliminary results show that the scissors mode plays a significant role in all transitions between accessible states of the studied nucleus. The photon strength functions describing well oar data arc compared to results from He-3-induced reactions, (n,gamma) experiments on Gd isotopes, and (gamma,gamma') reactions.