Publication at Faculty of Mathematics and Physics |
2011
Abstract
Spectra of two-step cascades (TSCs) following thermal neutron capture in (159)Tb were measured. In order to obtain information about the quantities governing the gamma decay of (160)Tb - the photon strength functions and the level density - the experimental TSC spectra were compared with the outcome of simulations of the gamma cascade decay based on the validity of the extreme statistical model.
The results obtained lead to an inescapable conclusion that the M1 scissors vibrational mode plays a crucial role in the cascade gamma decay of the product nucleus (160)Tb. This finding represents the first evidence for the existence of the scissors mode in an odd-odd nucleus.