Two Regions of a Possible Drastic Change in the Structure of the Excited States of Any Nuclei

Abstract

From a comparison of the absolute intensities of individual two-step cascades with known intensities of their primary and secondary transitions following thermal neutron capture the cascade and total population abilities of up to \~100 levels of each of the nuclei: 40K, 60Co, 74Ge, 114Cd, 118Sn, 124Te, 137,138Ba, 150Sm, 156,158Gd, 165Dy, 168Er, 175Yb, 181Hf, 183,184,185,187W, 196Pt and 200Hg have been determined. These experimental data as well as the intensities of two-step cascades to the low-lying levels of these very nuclei can be restored within an accuracy of experiment if only the level densities with a clearly expressed "step-like" structure are used and a considerable local increase of the radiative strength functions of secondary transitions to the levels situated close to the breakpoints on the energy dependence curve of level densities and their quite significant decrease to the low-lying levels of the nucleus are taken into account.