Peculiarities of gamma cascades de-excited of compound states in the 4s-shell region

An extensive information about gamma transitions probabilities and levei schemes of 144Nd, 163Dy and 175Yb nuclei for energy excitation region up to 4 MeV has been obtained from (n, 2y) reactaon investigation on 143Nd, 164Dy and 174Yb by means of a new instalation for two-quanta gamma cascade research. The presenc; of significant nonstatnstical effects for ws-shell nuclei has been shown by the analysis of two-quanta-cascade probabilities Isub(γγ). This is caused probably by the fragmentation of sinqle-quasiparticle states. Last suggestion is confirmed for energy interval < 2 MeV by statisticaliy smgnificant correlation between Isub(;gγ) values and cross section values for 164Dy(d, p) and 174Yb(d, t) reactions populating the same final states. Perspective of the method for a search of gamma decay mechanism and of precompound states of nuclei is discussed