Abstrakt
Spectra of two-step gamma cascades following neutron capture in Gd-155,Gd-157 were measured using the two-HPGe-detector facility installed at a pure subthermal neutron beam of the LVR-15 reactor in Rez near Prague. The main objective of this experiment was to get new information on photon strength functions with the emphasis put on the role of M1 scissors mode vibration.
An analysis of accumulated gamma-ray spectra, made within the statistical model., leads to the conclusion that the scissors mode significantly affects gamma decay of all states of studied nuclei. The obtained results for energy, damping width and summed B(M1)up arrow strength of the scissors mode are compared with what has been deduced from neutron capture experiments performed at DANCE detector installed in Los Alamos National Laboratory, NRF data for the ground state scissors mode and from the data on He-3-induced reactions using the so-called Oslo method.